Laudator Temporis Acti

Adolf Harnack (1851-1930), The Mission and Expansion of Christianity in the First Three Centuries, tr. James Moffatt, Vol. I (London: Williams and Norgate, 1908), pp. 422-423:

As inscriptions and writings testify, Christians in East and West alike made an exclusive or almost exclusive use of the old pagan names in their environment till after the middle of the third century, employing, indeed, very often names from pagan mythology and soothsaying. We find Christians called Apollinaris, Apollonius, Heraclius, Saturninus, Mercurius, Bacchylus, Bacchylides, Serapion, Satyrus, Aphrodisius, Dionysius, Hermas, Origen, etc., besides Faustus, Felix, and Felicissimus. "The martyrs perished because they declined to sacrifice to the gods whose names they bore"!

Now this is remarkable! Here was the primitive church exterminating every vestige of polytheism in her midst, tabooing pagan mythology as devilish, living with the great personalities of the Bible and upon their words, and yet freely employing the pagan names which had been hitherto in vogue!

The entire discussion on pp. 422-430 is worth reading. See also M. Depauw and W. Clarysse, "How Christian was Fourth Century Egypt? Onomastic Perspectives on Conversion," Vigiliae Christianae 67.4 (2013) 407-435.