«الربا اثنان وسبعون بابا أدناها مثل إتيان الرجل أمه وإن أربى الربا استطالة الرجل في عرض أخيه»
The Prophet (peace and blessings be upon him) said:
"Usury (riba) has seventy-two doors. The least of them is equal to a man committing incest with his own mother, and the greatest usury is a man's tongue-lashing against the honour of his brother."
Hadith Referenceصحیح الجامع الصغیر / حرف الراء / 3537