Yahya ibn Yahya narrated to us, saying: Mu'awiyah ibn Sallam ibn Abi Sallam al-Dimashqi informed us, from Yahya ibn Abi Kathir, that Abu Qilabah informed him that Thabit ibn al-Dahhak informed him that he had given the pledge of allegiance to the Messenger of Allah, peace and blessings be upon him, under the tree, and that the Messenger of Allah, peace and blessings be upon him, said: "Whoever swears an oath by a religion other than Islam, lying, then he is as he said. And whoever kills himself with something, he will be punished with it on the Day of Resurrection. And there is no vow for a man concerning something he does not possess."