They are first mentioned by Irenaeus, who connects them with the Valentinians.
11.9, and was used by the Valentinians.
We learn further that Anicetus as a mark of special honour allowed Polycarp to celebrate the Eucharist in the church, and that many Marcionites and Valentinians were converted by him during his stay in Rome.
There are many indications early in the 2nd century of a tendency towards the recognition of a single Gospel; for instance, there are the local Gospels according to Hebrews, according to Egyptians; Marcion had but one Gospel, St Luke, the Valentinians preferred St John and so on; Tatian reduced the Four Gospels to one by means of a Harmony, and it is possible that something of the kind may have existed before he did this.
The demiurge of the Valentinians always clearly bears the features of the Old Testament creator-God.