This Bible contradiction is from the Skeptic's Annotated Bible.
When Saul prophesied among the prophets.
1 Samuel 10:11-12 View context
And it came to pass, when all that knew him beforetime saw that, behold, he prophesied among the prophets, then the people said one to another, What [is] this [that] is come unto the son of Kish? [Is] Saul also among the prophets?
And one of the same place answered and said, But who [is] their father? Therefore it became a proverb, [Is] Saul also among the prophets?
After Saul prophesied naked for a day and a night.
1 Samuel 19:24 View context
And he stripped off his clothes also, and prophesied before Samuel in like manner, and lay down naked all that day and all that night. Wherefore they say, [Is] Saul also among the prophets?