An Nisa’ Ayah 2

وَءَاتُواْ ٱلْيَتَـٰمَىٰٓ أَمْوَٲلَهُمْ‌ۖ وَلَا تَتَبَدَّلُواْ ٱلْخَبِيثَ بِٱلطَّيِّبِ‌ۖ وَلَا تَأْكُلُوٓاْ أَمْوَٲلَهُمْ إِلَىٰٓ أَمْوَٲلِكُمْ‌ۚ إِنَّهُۥ كَانَ حُوبًا كَبِيرًا ٢ Give orphans their wealth ?when they reach maturity?, and do not exchange your worthless possessions for their valuables, nor cheat them by mixing their wealth with your own. For this would indeed be a great sin.