Here "the sun" is a metonym for the light of the sun. AT: "Then I saw an angel standing in the light of the sun" (See: [[rc://en/ta/man/translate/figs-metonymy]])
# both free and slave, the unimportant and the powerful
The angel uses these two sets of opposite-meaning words together to mean all people. (See: [[rc://en/ta/man/translate/figs-merism]])