On his father's authority, said that his grandfather 'Abd Allah b. 'Amr reported the Messenger of Allah ﷺ as saying: The proviso of a loan combined with a sale is not allowable, nor two conditions relating to one transaction, nor profit arising from something which is not in one's charge, nor selling what is not in your possession.
قَالَ رَسُولُ اللَّهِ ﷺ لاَ يَحِلُّ سَلَفٌ وَبَيْعٌ وَلاَ شَرْطَانِ فِي بَيْعٍ وَلاَ رِبْحُ مَا لَمْ تَضْمَنْ وَلاَ بَيْعُ مَا لَيْسَ عِنْدَكَ