masc. proper name, Latinized form of Greek Theophilos, literally "dear to God; loved by the gods," from theos "god" (from PIE root *dhes-, forming words for religious concepts) + philos "loved, beloved" (see -phile).
also -phil, word-forming element meaning "one that loves, likes, or is attracted to," via French -phile and Medieval Latin -philus in this sense, from Greek -philos, common suffix in personal names (such as Theophilos), from philos "loving, friendly, dear; related, own," related to philein "to love," which is of unknown origin. According to Beekes, the original meaning was "own, accompanying" rather than "beloved."
<a href="https://www.etymonline.com/word/Theophilus">Etymology of Theophilus by etymonline</a>
Harper, D. (n.d.). Etymology of Theophilus. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/Theophilus