[Endnote 199:1] The applications of Scripture would be taken chiefly from the books of which some would be recent but others of an earlier date, and it can surely be no exaggeration to place the formation of the body of doctrine which they contained in the period 160-175 A.D.above mentioned.

I doubt whether a critic could be blamed who should go back ten years further, but we shall be keeping on the safe side if we take our _terminus a quo_ as to which these Gnostic writings can be alleged in evidence at about the year 160.
A genuine fragment of a letter of Valentinus has been preserved by Clement of Alexandria in the second book of the Stromateis [Endnote 200:1].

This is thought to contain references to St.
Matthew's Gospel by Dr.Westcott, and, strange to say, both to St.
Matthew and St.Luke by Volkmar.

These references, however, are not sufficiently clear to be pressed.
A much less equivocal case is supplied by Hippolytus--less equivocal at least so far as the reference goes.

Among the passages which received a specially Gnostic interpretation is Luke i.