the nails, and thrust my hand into his side, I will not believe." But when Jesus appeared later and invited Thomas to touch his wounds and behold him, Thomas showed his belief by saying, "My Lord and my God". Jesus then said, "Thomas, because thou hast seen me, thou hast believed: blessed [are] they that have not seen, and [yet] have believed." Names and etymologies The name Thomas (Koine Greek: Θωμᾶς) given for the apostle in the New Testament is derived from the Aramaic תְּאוֹמָא Tʾōmā ( Tʾōmā/Tāʾwma), meaning "twin" and cognate to Hebrew תְּאוֹם tʾóm. The equivalent term for twin in Greek, which is also used in the New Testament, is Δίδυμος Didymos. Other names The Nag Hammadi copy of 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. Some have seen in the Acts of Thomas (written in east Syria in the early 3rd century, or perhaps as early as the first half of the 2nd century) an identification of Thomas with the apostle Judas, Son of James, better known in English as Jude. However, the first sentence of the Acts follows the Gospels and the Acts of the Apostles in distinguishing the apostle Thomas and the apostle Judas son of James. Others, such as James Tabor, identify him as Jude, brother of Jesus mentioned by Mark. In the Book of Thomas the Contender, part of the Nag Hammadi library, he is alleged to be a twin to Jesus: "Now, since it has been said that you are my twin and true companion, examine yourself…" A "Doubting Thomas" is a skeptic who refuses to believe without direct personal experience — a reference to the Gospel of John's depiction of the Apostle Thomas, who, in John's account, refused to believe the resurrected Jesus had appeared to the ten other apostles until he could see and feel Jesus' crucifixion wounds. Feast days When the feast of Saint Thomas was inserted in the Roman calendar in the 9th century, it was assigned to 21 December. The Martyrology of St. Jerome mentioned the apostle on 3 July, 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. Traditionalist Roman Catholics (who follow the General