4:20
An-Nisa 20
Surah An-Nisa (النساء), verse 20 — reference 4:20. Arabic text with optional translation and free audio on Al-Qalam.
وَإِنْ أَرَدتُّمُ ٱسْتِبْدَالَ زَوْجٍ مَّكَانَ زَوْجٍ وَءَاتَيْتُمْ إِحْدَىٰهُنَّ قِنطَارًا فَلَا تَأْخُذُوا۟ مِنْهُ شَيْـًٔا ۚ أَتَأْخُذُونَهُۥ بُهْتَـٰنًا وَإِثْمًا مُّبِينًا
wa-in aradttumu is'tib'dāla zawjin makāna zawjin waātaytum iḥ'dāhunna qinṭāran falā takhudhū min'hu shayan atakhudhūnahu buh'tānan wa-ith'man mubīnan
But if you want to replace one wife with another and you have given one of them a great amount [in gifts], do not take [back] from it anything. Would you take it in injustice and manifest sin?