150AD JUSTIN: There is no other thing for which you blame us, my friends, is there than this? That we do not live according to the Law, nor, are we circumcised in the flesh as your forefathers, nor do we observe the Sabbath as you do. (Dialogue with Trypho 10:1. In verse 3 the Jew Trypho acknowledges that Christians ‘do not keep the Sabbath.’)
