Al-Fath · 48:10

10. Those who pledge the allegiance of Al-Ridwan to you, O Messenger, to fight the idolaters of Makkah, are only pledging allegiance to Allah, because He is the One Who instructed them to fight the idolaters and He is the One Who will give them recompense. The hand of Allah is over their hands at the time of the pledge and He is aware of them. Nothing of theirs is hidden from them. Whoever breaks his pledge and does not fulfil the promise he made with Allah to assist His religion, then his breaking his pledge and promise is to his own detriment. Allah is not harmed by that. Whoever fulfils his promise to Allah to assist His religion, Allah will grant him a great reward, which is Paradise.