What does the cryptic crossword clue "Commit to flames popular heretic for speaking out — consumed! (10)" mean?

The definition is "Commit to flames". The wordplay uses a homophone (sounds like). IN + homophone of “sinner”+ ATE The answer is INCINERATE.

Commit to flames popular heretic for speaking out — consumed! (10)

Guardian Cryptic #29023 | 14 Down | 2023-03-21 flower