Thomas, also known as Judas Thomas Didymus or Jude Thomas Didymus, was one of Jesus' twelve apostles and is included in each of the four apostolic lists. Thomas is also called Didymus (the twin) each of the three times he appears in the Gospel According to John. Thomas doesn't do much in the synoptic gospels but becomes important towards the end of John. Thomas agrees with Jesus about returning to Judea despite the dangers and protests during the Last Supper that they really don't know what's going to happen to him.
Thomas is most famous for how he is depicted in the Gospel According to John. He first appears as a symbol of strength, encouraging the others to follow Jesus to Judea where death awaits. Later he expresses doubts about following Jesus. Finally, after Jesus' resurrection, he is the "doubting Thomas" who refused to believe that Jesus really returned until he saw the scars and placed his fingers in Jesus' side.
Some Christian legends have Thomas being the only witness to the Virgin Mary being assumed bodily up into heaven. Origen says that Thomas went to evangelize to the Parthians, but evidence suggests that he may have gone much further -- all the way to India. When Catholic missionaries first arrived in India, they found a Christian community already there which they attributed to the evangelistic work of Thomas.
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