Here the reading of Matt.xi.27 is given in a form very similar to that of Justin, [Greek: oudeis hegno ton patera ei mae ho uhios, kai (oude Justin) ton uhion, ei mae ho pataer kai ho (ois] Justin) [Greek: an ho uhios apokalupsae].
This verse however is quoted by the early writers, orthodox as well as heretical, in almost every possible way, and it is not clear from the account in Irenaeus whether the Marcosians used an extra- canonical Gospel or merely a different text of the Canonical.
Irenaeus himself seems to hold the latter view, and in favour of it may be urged the fact that they quote passages peculiar both to the first and the third Gospel; on the other hand, one of their quotations, [Greek: pollakis epethuaesa akousai hena ton logon touton], does not appear to have a canonical original.
On reviewing these results we find them present a chequered appearance.

There are no traces of coincidence so definite and consistent as to justify us in laying the finger upon any particular extra-canonical Gospel as that used by Justin.

But upon the whole it seems best to assume that some such Gospel was used, certainly not to the exclusion of the Canonical Gospels, but probably in addition to them.
A confusing element in the whole question is that to which we have just alluded in regard to the Gospel of the Marcosians.

It is often difficult to decide whether a writer has really before him an unknown document or merely a variant text of one with which we are familiar.

In the case of Justin it is to be noticed that there is often a very considerable approximation to his readings, not in the best text, but in some very early attested text, of the Canonical Gospels.