The method by which the correct reading had to be determined was as much historical as it is with us at the present day.
A not dissimilar state of things is indicated somewhat less explicitly in regard to the first Gospel.

In the text of Matt.i.18 all the Greek MSS., with one exception, read, [Greek: tou de Iaesou Christou hae genesis outos aen], B alone has [Greek: tou de Christou Iaesou].

The Greek of D is wanting at this point, but the Latin, d, reads with the best codices of the Old Latin, the Vulgate, and the Curetonian Syriac, 'Christi autem generatio sic erat' (or an equivalent).

Now Irenaeus quotes this passage three times.

In the first passage [Endnote 330:1] the original Greek text of Irenaeus has been preserved in a quotation of Germanus, Patriarch of Constantinople (the context also by Anastasius Sinaita, but these words appear to be omitted); and the reading of Germanus corresponds to that of the great mass of MSS.