For an answer to the question of the
date of composition of the original Book of Thomas, i.e. how long it was
written before the terminus post quem non of the extant copy of the
translation of the text (first half of the 4th cent.), we hardly possess any
indications. The only thing that can be said is that its incipit presupposes
the Gospel of Thomas and that Book Thom. therefore must have originated after
the Gospel of Thomas. The date of the Gospel of Thomas, however, is itself
much disputed. It is thus pure guesswork which leads Turner to assume the first
half of the 3rd cent. as the date of origin of the Boom Thom. Koester is
equally justified in situating it already in the 2nd cent. At all events the
problem of the date of Book Thom. loses much of its importance in view of the
necessity of applying a literary-critical perspective, in which Book Thom.
emerges as merely a thin and superficial framing of a basic document which is
neither gnostic nor Christian; thereby we find ourselves in what to a certain extent
is a ‘timeless’ sphere. (Hans-Martin Schenke, “The Book of Thomas,” trans.
Einar Thomassen, in New Testament Apocrypha, ed. Wilhelm Schneemelcher,
2 vols. [trans. R. McL. Wilson; Louisville, Ky.: Westminster John Knox Press,
1991], 1:234)
