The verb renounce means to say formally or declare publicly that you no longer stand for that belief or support it.
Synonyms are abandon, reject, disown, or deny.
The word origins from Old French (late 14th century) renoncier meaning “give up, cede”, and Modern French (12th century) renoncer (source also from Latin renuntiare meaning “bring back word, proclaim, protest against, renounce”. It comes from re- meaning “against” plus nuntiare meaning “to report, announce”, from nuntius meaning “messenger”.
Ray’s parents renounced him for being a troublemaker in school.
He doesn’t want to renounce his only hope.
The martyrs stood firm and didn’t renounce their faith.