He was born a Jew and was called to be one of the twelve Apostles. His exact birth and death dates are unknown, but his feast day is celebrated on July 3.
His name in Aramaic is Toma, which in Hebrew is Teom, and when translated into Greek is Didymus, which means “the twin,” a title which could mean he had a sibling born at the same time he was or could mean “one like us.” At the Last Supper, when Christ told His disciples that He was going to prepare a place for them to which they also might come because they knew both the place and the way, Thomas pleaded that they did not understand, and they all received the beautiful assurance that Christ is the Way, the Truth, and the Life. St. Thomas is also mentioned as being present at Lake Tiberias when a miraculous catch of fish occurred.
But, perhaps St. Thomas is best known for his role in verifying the Resurrection of his Master. Thomas' unwillingness to believe that the other Apostles had seen their risen Lord on the first Easter Sunday has earned him the title of "doubting Thomas."
Eight days later, on Christ's second apparition, Thomas was gently rebuked for his skepticism and furnished with the evidence he had demanded - seeing in Christ's hands the point of the nails. Thomas even put his fingers in the nail holes and his hand into Christ's side. After verifying the wounds were true, St. Thomas became convinced of the reality of the Resurrection and exclaimed, "My Lord and My God," thus making a public Profession of Faith in the Divinity of Jesus. Jesus then said to him: “Because you have seen Me, Thomas, you have believed.” Now if Thomas had seen and touched the Savior, why did Jesus say this? Perhaps it was because Thomas saw something other than what he believed. For no mortal man can see divinity. Perhaps Thomas saw the Man Christ and acknowledged His divinity with the words: “My Lord and my God.” Faith, therefore, followed upon seeing. However, in all fairness to Thomas it should be pointed out that when Jesus first appeared to the other apostles, he first showed them his hands and his side, without anyone needing to ask because Jesus knew what they were thinking. It was Thomas who acted as one like us and articulated what others were thinking.
This is all that we know about St. Thomas from the New Testament. According to Eusebius, after the dispersal of the Apostles after Pentecost, Thomas and Bartholomew were sent to evangelize the Parthians, Medes, and Persians. According to the Acts of Thomas, St. Thomas is believed to have sailed to India in 52 A.D. to spread the Christian faith, and he is believed to have landed at the port of Muziris, Tamilakam (modern-day North Paravur) and Kodungalloor (in modern-day Kerala state) where there was already an established Jewish community at the time. The port was destroyed in 1341 due to a massive flood that realigned the coasts. He is believed by the large native population who call themselves “Christians of St. Thomas” to have established Ezharappallikal or Seven and a Half Churches in Kerala. These churches are at Kodungallur, Palayoor, Kottakkavu, Kokkamangalam, Niranam, Nilackal, Kollam, and the half church Thiruvithamcode.
According to the accounts of Marco Polo, Thomas was killed in an accident when a fowler shot at a peacock and struck Thomas instead. The Roman Martyrology says that he was pierced with lances around the year 72 A.D. at the command of the king. Following his death, some of his relics were taken to Edessa while the rest were kept in India. They can still be found within the San Thome Basilica in Chennai, Mylapore, India. The relics taken to Edessa were moved in 1258 to Abruzzo, Italy, where today they can be found in the Cathedral of St. Thomas the Apostle in Ortona, Italy. However, it is believed that Saint Thomas' skull rests in the Monastery of Saint John the Theologian on the Greek Island of Patmos. Since at least the 16th century, St. Thomas Mount has been a common site revered by Hindus, Christians, and Muslims.
Saint Thomas was mentioned in several other texts, including one document called The Passing of Mary, which claims that the Apostle Thomas was the only one to witness the Assumption of Mary into heaven, while the other apostles were transported to Jerusalem to witness her death. While the other apostles were with Mary, Thomas was left in India until after her first burial, and he was later transported to her tomb and saw her bodily assumption into heaven, but he recovered her girdle which was left behind. In some versions of the story, the other apostles doubted Thomas' words until Mary's tomb was discovered to be empty with the exception of her girdle.
The Gospel of Thomas begins: "These are the secret sayings that the living Jesus spoke and Didymus Judas Thomas recorded." Early Syrian traditions also relate the apostle's full name as Judas Thomas. There is also the Acts of Thomas, which was written in east Syria in the first half of the 2nd century and identifies Saint Thomas as a relative of the apostle Jude, the brother of James. Few texts speak about Thomas' twin. In the Book of Thomas the Contender, the twin is identified as Jesus himself: "Now, since it has been said that you are my twin and true companion, examine yourself…”
When the feast of Saint Thomas was first inserted into the Roman calendar in the 9th century, it was assigned to December 21. However, the Martyrology of St. Jerome mentioned the apostle on July 3, the date to which the Roman celebration was transferred in 1969 so that it would no longer interfere with the major ferial days of Advent. St.Thomas is invoked against doubt and is considered the patron saint of architects; blind people; builders; construction workers; geometricians; masons; India; Pakistan; Sri Lanka; people in doubt; stone masons; stonecutters; surveyors; and theologians.
His symbols are the spear and lance; carpenter's square and lance; builder's rule; arrows; five wounds of our Lord; girdle; book and spear; spear; t-square. In Sacred art, Saint Thomas is commonly depicted as a young man holding a scroll, or as a young adult touching the resurrected Christ's wounds. Thomas and the girdle were often depicted in medieval and early Renaissance art, and he is often depicted with a lance (because of his martyrdom) or with a square (because of the legend that he was sent as an architect to the king of India).