Because Jesus rose from the dead. This initial answer to that question might sound blunt and certainly as if it needs some more explanation, which I will be happy to oblige the reader with.
The world is full of religions. They probably all have places that are sacred to them, some of which could be identified as places of worship to whatever deity or deities the religion or faith subscribes to.
However, if it were not for the content of the initial statement, we Christians would not have churches. Christianity, as the religion or faith many of us know, grew out of Judaism. Judaism, since the time of Moses, had one central place of worship for the whole group of people that came to be known as the children of Israel. The 400 year period after the return to Israel of the exiles after a 70 year absence, mainly from Babylon, and Persia, saw secondary local places of learning and worship known as synagogues also develop. These could be formed where there was a group of 10 male Jews who wanted to unite in this way.
Now, if Christ had not risen, there would be no Christianity. The closest there would be to the Christian Faith would still be Judaism, and we would still all be meeting in synagogue only at this time of history, as there has been no temple since the Romans destroyed it when they sacked Jerusalem in 70 CE.
No, if you know your history, you know that Jesus' teachings aroused such animosity among the Jewish leaders and those whom they could enlist to support them, that they persuaded the Roman authorities that Jesus deserved death by crucifixion. That would have been the end of the group that was following Jesus as a rabbi or teacher, as they called him,. These disciples and followers would no doubt have disappeared into the general body of Judaism. Hopefully, the teachings they had absorbed from Jesus would have helped make them better Jews, and perhaps there were some of whom that could be said.
However, to the shock of everyone, including Jesus' closest followers, the 12 disciples and others who had walked the streets and roads of Palestine with him, on the third day after the crucifixion, the tomb into which Jesus had been placed was empty. Some who visited the tomb claimed that they saw angels who told him that Jesus had risen, as he had predicted. Indeed, Jesus had been telling his disciples this would happen but resurrection in this life was not in the Jews’ scope of understanding at the time. There was a belief in resurrection after death, to a new life in what we generally speak of as ‘heaven.’ However, apart from a few miracles documented in their history where a prophet raised someone back to life, there had never been a resurrection of an individual of the individual’s own accord, if we can say that of Jesus' resurrection.
Many, from day one, never believed that Jesus rose from the dead. However, after 2000 years of ‘Christian’ life and stories or testimonies that sometimes led to martyrdom, I believe those who cling to this disbelief simply do not want to believe. The call on their lives if they did believe is not something they wish to consider. However, many more intelligent minds than mine, legal minds, have looked at the evidence and determined it is irrefutable by all legal standards. There might have been over a hundred in Jerusalem who saw Jesus in the first days. He evidently made a special appearance to his brother James, who seemed to turn from a skeptic to the leader of the church in Jerusalem. How’s that for impact of an appearance? The Apostle Paul, who documents some of these appearances outside of what we see in the Gospels and Acts of the Apostles, lists these appearances and says at one time Jesus even appeared to a crowd of 500. That sounds like in pre-resurrection days, when he seemed to draw crowds of thousands to his teachings and miracle working.
According to the Gospels, Jesus rose on the first day of the week, our Sunday. That was when he first appeared to his closest followers, then again a week later. That seems to have led to a continued pattern of those who had followed Jesus, as well as the many new converts that were quickly made after Pentecost, fifty days later, to meet on Sundays. That pattern has never been broken.
Unfortunately, as with many things, Sunday meeting has become for too many a tradition, a ritual. It lacks vitality. For others in our time, the focus has become the style of worship, the music. Some focus on the pastor’s message. Others go to meet friends. We try all kinds of strategies to use Sunday mornings to draw more people into our faith communities. Maybe all of this is missing the key point.
Meeting on Sundays is a testimony, a witness, to a risen Jesus. It confirmed him as the promised Messiah, or Christ, the Son of God. Moreover, it is also a witness to the power of God the Father, who brought Jesus back to life. It is also a witness to the third person of the Trinity, which Christians believe is the nature of God, the Spirit. This would be because there was a special infilling of the disciples of Jesus, including his mother, by the Holy Spirit at Pentecost, a Jewish feast fifty days after Passover. That first Pentecost after Jesus’ resurrection is also believed to be on a Sunday.
Three good reasons to celebrate and worship on Sunday. These should be the real reasons we ‘go to church’. We go to thank God for all of this. We go to share stories of how the Risen Christ, through the Spirit given us who believe in him, has changed our lives, sometimes in drastic ways. Thus, we go to meet with fellow believers to have our own faith encouraged and strengthened by what we do together on Sunday mornings. Perhaps if we do all of this with the enthusiasm of the Spirit in us as it was in our sister and brothers 2000 yer ago, people would be draw in by the question, ‘What is happening there?’
