The presence of this reading in the Old Latin and Curetonian Syriac proves its wide diffusion.

At the same time it is clear that Irenaeus himself was aware of the presence of the other reading in some copies which he regarded as bearing the marks of heretical depravation.
It is unfortunate that fuller illustration cannot be given from Irenaeus, but the number of the quotations from the Gospels of which the Greek text still remains is not large, and where we have only the Latin interpretation we cannot be sure that the actual text of Irenaeus is before us.

Much uncertainty is thus raised.
For instance, a doubt is expressed by the editors of Irenaeus whether the words 'without a cause' ([Greek: eikae]--sine caussa) in the quotation of Matt.v.22 [Endnote 331:1] belong to the original text or not.

Probably they did so, as they are found in the Old Latin and Curetonian Syriac and in Western authorities generally.

They are wanting however in B, in Origen, and 'in the true copies' according to Jerome, &c.