Surat An-Nahl (The Bee) - النحل

وَأَوْفُوا۟ بِعَهْدِ ٱللَّهِ إِذَا عَٰهَدتُّمْ وَلَا تَنقُضُوا۟ ٱلْأَيْمَٰنَ بَعْدَ تَوْكِيدِهَا وَقَدْ جَعَلْتُمُ ٱللَّهَ عَلَيْكُمْ كَفِيلًا إِنَّ ٱللَّهَ يَعْلَمُ مَا تَفْعَلُونَ ﴿٩١﴾

And fulfill the covenant of Allah when you have made a covenant, and do not break the oaths after making them fast, and you have indeed made Allah a surety for you; surely Allah knows what you do.