When I have a question about a doctrine, I like to define the terms first. I think that I recognized Acts 2:38.
The word "repent" came up along with believe.
Believe is mentioned in the book I'm reading right now, John. It's used andtranslated "faith" in other parts of the Bible.
Ie. John 3:16 whosoever believeth in Him should not perish, but have everlasting life.
Epesians 2:8 For by grace are ye saved by faith.

Both come from the same Greek word.