وَأَوْفُوا۟ بِعَهْدِ ٱللَّهِ إِذَا عَٰهَدتُّمْ وَلَا تَنقُضُوا۟ ٱلْأَيْمَٰنَ بَعْدَ تَوْكِيدِهَا وَقَدْ جَعَلْتُمُ ٱللَّهَ عَلَيْكُمْ كَفِيلًا ۚ إِنَّ ٱللَّهَ يَعْلَمُ مَا تَفْعَلُونَ
And fulfill the covenant of Allah when you have taken it, [O believers], and do not break oaths after their confirmation while you have made Allah, over you, a witness. Indeed, Allah knows what you do.
Uthmani script · Saheeh International · Quran 16:91