heresy in Christianity: "From the Jew the heretic has accepted guidance in this discussion [that Jesus was not the Christ]." This is largely because Tertullian does not consider Christianity as an additional religion but rather a continuation of Judaism with the Jewish messianic component fulfilled.

The use of the word heresy was given wide currency by Irenaeus in his 2nd-century tract Contra Haereses (Against Heresies) to describe and discredit his