180 CE

Bishop Irenaeus of Lyons champions the fourfold canon, linking the four gospels to the four cherubic beasts.

Composition of 'Against Heresies' (Adversus Haereses) by Irenaeus of Lyon in Greek, establishing the proto-orthodox defense against Valentinus.

Irenaeus of Lyons cites the Shepherd of Hermas as authoritative scripture in Against Heresies (4.20.2).

Irenaeus of Lyons establishes the theological necessity of the fourfold gospel canon.

Irenaeus of Lyons establishes the theological necessity of the fourfold gospel canon.