1. The Upper Room of Mark in Jerusalem: The Site of Resurrection Faith
The Upper Room of Mark in Jerusalem holds a special place in Christian church history and is known for providing deep spiritual insights to today’s church community. This upper room serves as the setting for a very important scene spanning Acts 1 and 2: it is traditionally believed that the early church took shape there and that the Holy Spirit descended there. In addition, Acts 1 describes the events right before Jesus’ ascension—when the resurrected Jesus, completing His earthly ministry, gives His disciples final instructions and promises. More than just a physical space, this Upper Room symbolizes “the place where the early church gathered in the midst of fear right in the heart of Jerusalem and sparked a historical shift.”
Pastor David Jang refers to this scene by saying, “Although the disciples were trembling with fear, the resurrected Jesus came to them personally for about 40 days, restored them, and infused faith into them before gathering them again in Jerusalem.” The disciples had scattered as far as Galilee, but after meeting the resurrected Lord, they finally returned to Jerusalem armed with “resurrection faith.” This vividly shows how the resurrection operates powerfully within a faith community, with the Upper Room of Mark as the starting point of this experience.
Why, then, did it have to be Jerusalem? It was in Jerusalem that Jesus was arrested and executed. For the disciples, it was a place filled with terrifying and tragic memories. After Jesus was crucified, many of His followers scattered. However, Jesus specifically said, “Do not leave Jerusalem, but wait for the gift my Father promised” (Acts 1:4–5), thereby instructing the disciples to return to the most dangerous and frightening city. Pastor David Jang interprets this by saying, “God’s work always transcends our expectations and common sense. Resurrection faith becomes evident when it exerts the greatest hope in the most desperate place.”
A key characteristic of resurrection faith is the conviction that “death is not the end.” Though the disciples had once been paralyzed by the fear, “The Lord has been executed, and we too might be captured and killed,” they encountered Jesus, who had truly broken the power of death and risen again, thus experiencing “a new era beyond death.” Therefore, Acts 1:3 testifies that for 40 days after His resurrection, Jesus “spoke about the kingdom of God.” This reference to “the kingdom of God” is not merely an abstract eschatology or philosophy. It includes the practical direction on how the church should be established in power in the present reality and how it should move forward. One of its core directives is “You are to start in Jerusalem.”
Pastor David Jang states, “We can define the history of being restored in the very place where people have become the weakest and have fallen as ‘the actual reality of resurrection faith.’” This, he emphasizes, is the lesson from the Upper Room of Mark. When the disciples first gathered in that upper room, the atmosphere must have been very subdued. Immediately following the crucifixion, Jesus’ body was laid in a tomb, and the religious leaders were eager to wipe out every trace of His followers. Thus, that upper room may have functioned as a “temporary safe house for prayer.” But Jesus said, “Do not stop there; wait— not in the sense of standing still, but remain until you receive the Holy Spirit.” The transformation of the Upper Room, from a “helpless hideout” into the “origin of power,” is explained by the coming of the Holy Spirit.
Once the Holy Spirit descended (Acts 2), they were no longer a group of frightened disciples hiding away. The same upper room that had been a place of fear became the very site where the certainty of the resurrection and the power of the Holy Spirit descended, and the disciples left that room to boldly preach the gospel in the streets of Jerusalem. According to Pastor David Jang, “If the resurrection remains only a doctrine, it holds no real meaning. But when resurrection faith becomes the power that overturns people’s actual lives, we finally witness a change in which even within the walls of Jerusalem, people overcome fear and act.”
Such “faith in action” appears throughout the Book of Acts. Beginning in Jerusalem, the gospel spreads to Samaria, throughout all Judea, and on to the ends of the earth. The first clear instance of faith translated into action is seen in Acts 2, the event of Pentecost. Those who had been huddled in an inner room went out into the streets to proclaim the gospel, resulting in the dramatic scene of several thousand people repenting and being baptized in a single day. The spark of this movement was the Upper Room of Mark.
This upper room has also been likened to the “womb” or “birthplace” of the church. The reason is that a new era began, much like the birth of new life, made possible by the conviction of the risen Jesus and the descent of the Holy Spirit—effectively “conceiving” a brand-new community within that space. When Jesus was still physically with them, the disciples were in a phase of learning (being discipled) by following Him. But after Jesus’ ascension and the descent of the Holy Spirit, the disciples became “pillars of the church community,” taking on the active role of expanding the gospel. The Upper Room was at the heart of that pivotal transition, powered by resurrection faith.
Recalling Peter’s restoration in John 21 helps us understand how the disciples encountered the resurrected Jesus, rediscovered their calling, and then returned to Jerusalem in obedience. After Peter denied the Lord three times, Jesus asked him three times, “Do you love Me?” and upon Peter’s affirmation of love, the Lord reconciled Peter to himself, allowing him to be “reborn” as the “rock” (Peter). Pastor David Jang says of this scene, “The church does not run on particular programs or organizational capabilities; rather, its fundamental driving force is ‘love for the Lord.’ That love originates from the Lord’s resurrection, and it solidifies only when we believe in our hearts and confess with our mouths the grace He showed by embracing us.”
The Upper Room of Mark was a collective place of such “confession,” “repentance,” and “faith.” Disciples who had once denied Him and scattered came back together into one community, able to muster up courage beyond despair—all because of the Lord’s resurrection and the promise of the Holy Spirit. Pastor David Jang reiterates, “When the events described in Matthew 26 and onward (the passion of Jesus), John 21 (the disciples returning to Galilee), and Acts 1 (the return to Jerusalem) are woven together, resurrection faith gives a truly practical message to the church today.”
In this way, the Upper Room of Mark ultimately became a place of transition “from fear to boldness, from scattering to gathering, and from shame and denial to repentance and confession.” The contemporary church must meditate deeply on this point. If “the church, at some moment, only hides away in fear of societal criticism or persecution,” then we need again the flame of the Holy Spirit that descended on the Upper Room of Mark. This is also the modern application of resurrection faith. Holding on to the fact that the resurrected Jesus has destroyed death and is still “building the church” as though He is with us, supporting His church to boldly proclaim the gospel in the midst of the world, we can continue with joy “from Jerusalem to the ends of the earth.”
From this overall context, Pastor David Jang stresses, “We must not view the Upper Room of Mark simply as a historical location; rather, each local church today must recover its own ‘upper room.’” That place could be “the space where we long for the presence of the Holy Spirit and pray,” or “the place where we hold onto and confess resurrection faith together.” Gathering in the upper room to pray is not about hiding from the world; it is about “receiving power there in order to go forth into the world,” which is the essential point. As Jesus told His disciples, “In a few days you will be baptized with the Holy Spirit” (Acts 1:5). Since that promise was fulfilled “in the upper room,” the early church never disappeared but instead spread throughout the whole world.
2. The Selection of Matthias: The Church’s Recovery to Fill Judas’ Empty Place
In the latter part of Acts 1, the disciples face the event of appointing someone new to the position of the twelfth apostle. Between Easter and Pentecost, one of the major issues was “what to do about the betrayal by Judas Iscariot—one of the Twelve originally called by Jesus—and the aftermath.” Judas had handed Jesus over for thirty silver coins and afterward hanged himself. Furthermore, Scripture (Acts 1:18) records that he bought a field with the reward for his wickedness, fell there, and his body burst open, causing him to become a symbol of the “tragedy of blood money.”
Pastor David Jang describes Judas’ tragedy as “the very person in the closest position committed the greatest crime.” Judas held the money bag among the disciple community, effectively managing their finances and serving in an important capacity. Likewise, in the church today, positions involving finances and service should be filled by those with abundant grace, but these roles can also become an easy avenue for Satan’s temptations and tests. Because money is needed to run a community, it can lead to worldly profit or stir up personal ambition. Hence, the Bible repeatedly warns the church that “the love of money is a root of all kinds of evil” (1 Timothy 6:10), and records that the early church “shared all their possessions and gave to each as they had need” (Acts 2:45, 4:34), clarifying its focus on not falling into corruption through entanglement with material wealth.
Yet Judas, tempted by material greed and political calculations, became a tool of Satan, ultimately betraying Jesus. Although he regretted his action shortly after the betrayal, it did not lead to genuine repentance. Instead, he ended his life in extreme despair, leaving the church with the painful wound of “losing one of the disciples.” The Twelve symbolized the twelve tribes of Israel—an essential spiritual foundation—and were like the “doors” of the new covenant community that the Lord Himself had established. With one of these “doors” fallen, it became critical to rebuild this entrance.
Hence, Acts 1 shows us the meeting during which they filled that vacancy. The early church sought someone to take the apostolic position, and the candidate chosen was Matthias. Observing this process provides a window into how the church deals with crises. In Acts 1:21–22, Peter proposes, “We must choose one of those who have been with us the whole time… one of these must become a witness with us of His resurrection—someone who was with us, beginning from John’s baptism to the time Jesus was taken up from us.” As a result, two individuals were put forward, and the early church cast lots, eventually selecting Matthias.
Pastor David Jang highlights several notable points here. First, the early church placed “being a witness of the resurrection” as the top requirement. The church exists to testify to the risen Lord, so the core mission of an apostle was likewise to proclaim the resurrection. Matthias and the other candidate were people who had witnessed Jesus’ entire public ministry—His suffering, death, and resurrection—right alongside the other apostles. Second, the combination of communal consensus, prayer, and finally casting lots is striking. It shows “the importance of everyone’s input and the community’s agreement, with the final decision placed in God’s sovereign hands.” This indicates that the church does not choose its leaders through mere human calculation or political compromise. Third, although Scripture does not record in detail what special works Matthias performed afterward, through this appointment the complete group of twelve apostles was restored, and they were ready to receive the Holy Spirit at Pentecost.
Why was this selection process so important? Because the church’s very first task before the Spirit’s coming was “to restore the apostolic team.” Without healing the vacuum and the hurt caused by Judas’ betrayal, the church could not have become perfectly united. The wound of “one of our own betrayed the Lord” likely lingered in people’s hearts, so rebuilding their trust in each other was urgent. Additionally, the disciples who had scattered came back together in Jerusalem to pray, forming a united front committed to ensuring “such betrayal must never happen again.”
Pastor David Jang points out, “Judas’ betrayal shows symbolically how a leader’s betrayal can devastate a community.” That is why the early church did not simply forget or cover up Judas’ story; rather, at the very beginning of the church’s public existence, they dealt with it transparently. The blood money was thrown into the temple treasury, and a “Field of Blood” was purchased (Matthew 27:5–8). This disgraceful history was not concealed; in fact, it was revealed publicly. Relying on prophecy (whether from Jeremiah or Psalms), they accepted that “this event was part of the fulfillment of prophecy,” and the whole community prayed in one accord before appointing a new member.
Thus, Matthias took over Judas’ apostolic seat. The church restored the framework of the Twelve, and within their fortified spiritual unity, they awaited the Pentecost outpouring of the Holy Spirit. When that Spirit descended, the apostles launched the gospel outward from Jerusalem into all Judea and Samaria and eventually the ends of the earth. Had the church ignored the internal strife and the wound inflicted by Judas’ betrayal and death, it could have disintegrated before it even began. Instead, the church exposed the wound, addressed it, and publicly proclaimed its path to restoration—this paved the way for the church to be reborn more maturely.
Another perspective is that Judas’ mistake and death instilled in the early church a sense that “no one can ever become complacent on this path.” Even someone who followed Jesus for three years, witnessed miracles and teachings, and was entrusted with the money bag could fall. Therefore, no one in the church is immune to the danger of temptation. Pastor David Jang warns regarding this point, “The same applies to modern church leadership. No matter how gifted someone appears, we must continually examine ourselves under the Word and the Holy Spirit, staying awake in prayer. Otherwise, Satan can seize on any weakness.” Indeed, church history has no shortage of betrayal and moral failures. Yet, each time, God raised new individuals (like Matthias) to fill the church’s vacant places and continue its story.
What, then, can today’s church learn specifically from Matthias’ selection? First, the church must fill pivotal leadership positions through communal agreement and prayer. It cannot choose leaders based on ability, fame, or political maneuvering, but must ask, “Do they fully embrace resurrection faith?” “Have they walked with the Lord?” “Have they witnessed the Lord’s suffering, death, and resurrection closely, and can they testify with their lives?” Such core faith confessions are far more important than worldly factors. Second, when the betrayal of a leader or a major hurt occurs in the church, we should not simply label it as an “individual tragedy” and hide it. Instead, the entire community should grieve and seek together—in prayer and Scripture—how to recover. After Judas fell, the early church did not spend time bitterly condemning him. They studied Jesus’ words and the relevant prophecies, using that understanding to move forward in a way aligned with them. Third, the entire recovery process ultimately focused on “the descent of the Holy Spirit.” Why did the church go to such lengths to address this incident prior to receiving the Holy Spirit? Because they needed to be in a state of readiness—free of unrighteousness and chaos—to receive the Spirit of Pentecost. Pastor David Jang emphasizes, “Before talking about the Spirit’s work, revival, or growth, the church must first earnestly confront and deal with internal sin and injustice. If its leaders have fallen, the church must not hide it but genuinely seek a path of healing.”
If we view Judas’ failure and Matthias’ appointment as “a single symbol,” it conveys that “no matter what great wound the church sustains, under God’s plan it will find a path to recovery.” Of course, Judas was not predestined to be lost from the start; he chose his path and ended in eternal tragedy. The church invites everyone to the path of repentance and redemption, but if individuals persistently refuse, tragedy inevitably follows. Instead of simply covering up such tragedies, the church must find momentum for repentance and renewal, forging a new path. In this process, “resurrection faith” emerges as the key driving force.
Resurrection faith is the belief in “God’s power to overcome death and restore life.” Judas was the one who brought about Jesus’ death, and he was consumed by guilt, but Jesus overcame death by rising again, revealing the path of life. The shock and fear the church felt from Judas’ betrayal were ultimately overcome by the hope found in Jesus’ resurrection. When Matthias filled the empty spot, the Twelve were reunited and ready to receive the Holy Spirit. Then, empowered by the Holy Spirit, they proclaimed the gospel boldly in Jerusalem. Reading Acts 1 through 4, we see Peter and John standing before the temple guards and religious authorities without fear, declaring, “Salvation is found in no one else” (Acts 4:12). This is the same Peter who once denied Jesus three times before the rooster crowed. Now he was transformed in the Upper Room of Mark, filled with the Holy Spirit, and representing the “complete apostolic circle” that included Matthias, boldly preaching the gospel. This underscores the powerful message that “Even the vacancy left by a collapsed leader was restored by God.”
Pastor David Jang states, “As the church lost Judas and gained Matthias, it was as if the ‘bloodied wound’ was healed, and likewise, modern churches must continually receive healing for old wounds and pains in order to be filled with new wine.” This lesson applies not just to the early church but also to the modern church, which still experiences conflicts, corruption, and betrayals of various kinds. Each time, we must ask how we will “raise up new Matthias-like leaders” to restore the community and be receptive to the work of the Holy Spirit.
The church is “the community that ushers in a new era through the Holy Spirit,” and at the same time, it grows by traversing numerous intersections of “betrayal and repentance, death and resurrection, discouragement and renewal.” Judas Iscariot hastened Jesus’ death; Matthias filled his vacant place and expanded the door of the gospel. Peter denied and fled, but Jesus sought him out in John 21, restored his love, and in Acts he emerged as the foremost preacher among the apostles. After reestablishing the apostolic leadership, the early church experienced the mighty descent of the Holy Spirit in the Upper Room of Mark. From the moment the Spirit came, they no longer hid. They went into the public square to preach the gospel, and soon all of Jerusalem was in an uproar.
Can the church today have the same experience? Pastor David Jang believes, “Certainly yes. However, the condition depends on whether the church truly believes in the actual power of resurrection faith today, resolves its internal issues (betrayal, corruption, mistrust) through repentance and prayer, and fully seeks the Spirit’s leading.” The Upper Room of Mark and Matthias’ selection are prime examples of how the church can tangibly experience the risen Lord’s power and overcome internal conflict and hurt, opening the way into a new era.
The core of Christian faith, epitomized by the resurrection, is the belief that “death, despair, and failure in this world are never the final word.” Even though the case of Judas seems utterly hopeless, the church carried on the long history of gospel proclamation through Matthias. Even if we, like Peter, sometimes deny the Lord and live in guilt, the story in John 21 shows that the Lord personally comes to us again to restore us. By that grace, we are drawn into the Upper Room of Mark, not to remain in a powerless state but to be clothed in the bold power of the Holy Spirit so that we can go out into the midst of the world.
Through such a journey, the early church concludes at the end of Acts 28 with the triumphant note that Paul “proclaimed the kingdom of God without hindrance,” implying that no one could stop the gospel. Paul preached from prison in Rome, and Peter, according to historical tradition, ended his life in martyrdom by crucifixion upside down. Even so, countless disciples rose to fill his place. Though the church has periodically been shaken and has faltered, it stands up anew in resurrection faith and the Spirit’s power. Even if one of the Twelve collapses, God can still restore apostolic ministry and carry it on to the ends of the earth.
Matthias’ selection embodies both “restoration” and “forward progress.” It was the starting point for the church to overcome its internal wounds and, based on resurrection faith, reach for a greater vision. This lesson still resonates with us today, and church leaders facing various challenges in their ministry settings often ask, “How did the early church overcome such trials?” The answer invariably points to “a firm confession of resurrection faith, seeking the presence of the Holy Spirit in prayer, and transparent communal procedures.”
Summarizing this, Pastor David Jang states, “Resurrection is power. When that power works within our hearts, it brings life to individuals and the church, building up the body of Christ. No matter how severe the betrayal, the church can find a way forward through recovery and new beginnings. Judas’ failure did not signal the end of church history, and neither will any major wound we face today extinguish the promise of God’s kingdom.”
This is the critical reason why “the Upper Room of Mark and the selection of Matthias” are connected. The Upper Room of Mark was the ignition point where the disciples, once hidden in fear, experienced the descent of the Holy Spirit and began to preach the gospel. The choice of Matthias was the scene in which the church became a “complete community” again after one apostle’s betrayal and death. Both narratives combine to show “how denial, betrayal, and fear within the church are transformed into restoration and the demonstration of God’s power through the Lord’s resurrection and the Holy Spirit’s presence.” These stories encompass sorrow and remorse, yet they are filled with a greater measure of God’s grace. Consequently, the early church arose resolutely to spread the gospel beyond Jerusalem to the far reaches of the earth.
It is the same for today’s church. If any local congregation or community recovers its own “modern-day upper room,” becoming filled with resurrection faith, and if it transparently heals the wounds left behind by a “Judas” in their midst—much like they appointed Matthias—the church can expect a renewed work of the Holy Spirit. The Pentecost event was not a one-time historical occurrence confined to a specific place 2,000 years ago; it is God’s ongoing movement that every church in every era and location can experience.
This teaching aligns with Pastor David Jang’s long-standing emphasis on the “practical dimension of resurrection faith.” If Jesus’ resurrection is accepted only intellectually, it merely remains a doctrine. But the early church demonstrated how this resurrection served as the vital driving force in real life—showing that betrayal, suffering, death, and despair no longer hold the final say. Peter and the apostles boldly preaching in front of the very powers that had sought to kill them demonstrates just how concrete and explosive the power of the resurrection truly is.
Hence, to the question, “What is the church?” we might answer, “It is the community that began in the Upper Room of Mark in Jerusalem, overcame Judas Iscariot’s betrayal by appointing Matthias, received the Holy Spirit at Pentecost, and then spread to every corner of the globe.” This identity transcends the boundaries of history and geography and remains valid today. As long as the church keeps its resurrection faith, its doors never close. Even if internal ruptures occur, God raises up new individuals to restore that place and continues to pour out His Spirit. This continuity of the gospel—“from Jerusalem to Rome, and to all the earth”—is the inheritance of faith that today’s church must embrace.
Pastor David Jang’s concluding exhortation centers on this truth: “We must reclaim a present-day ‘upper room,’ and when betrayal or failure occur, we should not conceal them but rather seek genuine repentance and transparent resolution to seize the opportunity for a new beginning God offers. At the core of this stands ‘the Risen Lord,’ whose missionary mandate is carried out through the church.” When the church follows this path in obedience, the story of Acts does not end but continues to unfold.