The gospel is ascribed to the apostle Thomas, one of the twelve. What in fact do we know of this this Thomas? His full name was Didymus Judas Thomas. That is to say, Judas was his proper name, while the additions Didymus and Thomas (Te’omas) are descriptive adjuncts. Both mean “twin,” one in Greek and the other in Aramaic. This disciple then was a twin of someone. But of whom?
The apocryphal Acts of Thomas, apparently written in Syria in the third century, is the source of the legend that this disciple became a missionary in India. The text also asserts that Thomas was the brother of Jesus. Likwise, this claim appears in one of the gnostic Nag Hammadi documents.
For a long time, Catholics and others, eager to defend their notion of the perpetual virginity of Mary, have claimed that Jesus’ brothers were not truly uterine siblings, born of the womb of Mary, but cousins perhaps, or children of Joseph by another mother.
The New Testament texts do not offer support for these speculations. Instead, they speak directly of Jesus’ having brothers (and sisters as well, though they are not named). The fullest list of brothers (not necessarily exhaustive) is given in Matthew 13:55, where four are mentioned: James, Joseph, Simon, and Judas. It is unlikely that the last is the disciple who betrayed Jesus, as he is never identified as Jesus’ brother. This person could be the Jude to whom an epistle is ascribed in the New Testament. Yet there is a real possibility that the last brother named in Matthew’s list is our Didymus Judas Thomas.
On this interpretation Jesus had a twin brother, also born of Mary. One child was divine, the other an ordinary human being. This seems bizarre, yet the situation is not without precedent--at least in classical mythology. One parallel concerns the supreme Greek hero Heracles (Hercules), who had a mortal twin named Iphicles. According to the story, Alcmene had conceived a child with her husband, Amphitryon. Then she attracted the amorous attentions of Zeus, who made love to her in human form--in the guise of her husband Amphitryon. As a result of these couplings two children grew in her womb, one the son of a mortal, the other the son of a god.
Let us review the facts as presented in the legend. First came the “normal” impregnation: male human to female human. Then there occurred the extraordinary fertilization of the woman with the sperm of a god. The result of the first act was the mortal Iphicles. Herakles, whose heroic stature approached but did not quite attain the status of a god, resulted from Alcmene’s second coupling.
In the case of Mary we would need to reverse the order. First she was impregnated by the Holy Spirit, while still a virgin. Not long thereafter, Joseph (or some other man) impregnated her with the child who was to become Didymus Judas Thomas, Jesus’ twin brother. As the Trinity could not become a quaternity, Thomas was denied divine status.
Recent scholarship has explored many fascinating bypaths of Early Christianity. To the best of my knowledge, though, Bart Ehrman (in his book “Lost Christianities”) is the only one to have discussed frankly this extraordinary possibility--that Jesus had a twin brother. However, he does not explore the implications further.
Did Thomas acquire special knowledge of divine truths while still in the womb? Was it uncomfortable for him, having to share the cramped space with a divine being? Did Thomas received any of the gifts of the magi? What was his status in Joseph’s carpentry shop? And so forth.
These questions may seem facetious--and they probably are. But the theological implications of this twinship are enormous. They literally boggle the mind.