1232. hadíth
وَ قَالَ عَلَيْهِ اَلسَّلاَمُ: فِي اَلرَّجُلِ يَبِيعُ اَلْمَمْلُوكَ وَ يَشْتَرِطُ عَلَيْهِ أَنْ يَجْعَلَ لَهُ شَيْئاً قَالَ "يَجُوزُ".
Imam (a.s) said regarding a man who sells a slave and stipulates upon the buyer to give him something: "It is permissible."