According to the author of the book, this verse tells about a man named Abner who was leading a group of people, serving a king named Ishbosheth, as they traveled from one place called Mahanaim to another place called Gibeon. It is a part of a bigger story showing the actions and choices of people during a time when different leaders wanted to be king.
2 Samuel 2:12: And Abner the son of Ner, and the servants of Ishbosheth the son of Saul, went out from Mahanaim to Gibeon.
2 Samuel 2:12 describes a scenario involving war, whereas 1 Corinthians 14:33 states that God is not the author of confusion but of peace.
1 Corinthians 14:33: For God is not [the author] of confusion, but of peace, as in all churches of the saints. [confusion: Gr. tumult, or, unquietness]