1. Aeschylus, from "Aeschylus," by John Herrington:
record of his first dramatic production in ca. 498 B.C., and a legend,
which runs as follows: 'Aeschylus used to say that once, when he was a
teenager, he was guarding the grapes in the countryside and fell asleep.
Dionysus appeared standing over him and told him to compose tragedy.
When daylight came, since he wanted to obey the god, he tried it, and
found it easy from that moment on."
2. Joseph Brodsky, from "Against Forgetting," edited by Carolyn Forche:
"In February 1964, Brodsky, who had left school at fifteen, was tried in Leningrad as a 'social parasite' who had corrupted young people with his 'pornographic' and anti-Soviet verse. In response to the judge's questions about where he had received the authority to write poems, he answered, 'From God.'"
3. I will add others as I find them. Commenters, any additions?