Eusebius of Caesarea

But even if we are clearly something new, and this truly recent name of Christians has only recently been known among all the nations, our life and manner of conduct in accordance with the very teachings of our religion have not been recently fashioned by us, but, as it were, from the first creation of humanity have been established by the natural concepts of the God-favored people of old.… And by deeds more manifest than words is Abraham's manner of religion shown to be practiced at present among Christians alone.