The Gospel of Thomas is a collection of traditional Sayings (logoi) of Jesus. It is attributed to Didymos Judas Thomas, the "Doubting Thomas" of the canonical Gospels, and according to many early traditions, the twin brother of Jesus ("didymos" means "twin" in Greek).

There has been much speculation on the relationship of Thomas to the canonical Gospels. Many Sayings in Thomas have parallels with the New Testament Sayings, especially those found in the synoptic Gospels. This leads many to believe that Thomas was also based on the so-called "Q" Document, along with Matthew, Luke, and Mark. Indeed, some have speculated that Thomas may in fact be "Q". Unlike the synoptic Gospels, and like "Q", the Gospel of Thomas has no narrative connecting the various Sayings. In form, it is simply a list of 114 Sayings, in no particular order. Comparison with New Testament parallels show that Thomas contains either more primitive versions of the Sayings, or developments of more primitive versions. Either way, Thomas seems to preserve earlier traditions about Jesus than the New Testament...