Nor should it appear strange, if one who departeth from this life is said to be born. For as a man is said to be born when he comes out of his mother’s womb into the light of day, so may he be said to be born who from out of the prison of the body, is raised to the light eternal. Whence the festivals of the saints, which are the days on which they died, are called their birthdays.
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).
Also cites: in Hom. Dom. Sec. post. vet. Pasch.