Thabit bin Adh-Dahhak:
That he took oath of allegiance to the Messenger of Allah (ﷺ) under the tree. The Messenger of Allah (ﷺ) said: If anyone swears by religion other than Islam falsely, he is like what has has said. If anyone kills himself with something, he will be punished with it on the Day of Resurrection. A vow over which a man has no control is not binding on him.