Asclepius is the healer god, son of Apollo and a mortal mother, and his cult would grow in late antiquity to be the most serious competitor with Christianity in the eastern empire for the loyalty of the sick. The temples of Asclepius at Epidaurus and Pergamon practiced incubation, where the sick slept in the precinct and were given dreams in which the god prescribed treatment. Inscriptions from these sites survive recording cures. Justin Martyr in his Apologies takes Asclepius seriously enough to argue against him directly. The cult of relics in Christian shrines, where pilgrims slept near the tomb of a saint hoping for healing dreams or miracles, took up the same physical practice within a different theology.