وَقَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ : " عَلَى الْيَدِ مَا أَخَذَتْ حَتَّى تُؤَدِّيَ " .
And the Prophet (peace and blessings be upon him) said: Whatever a hand takes (from another), it remains a liability upon it until it is returned (to the giver).