Al-Kāfi - The Book of Commerce

Al-Kāfi - The Book of Commerce Chapter: The Case of Change of Prices of Certain Merchandise before Delivery َّدُ بْنُ يَحْيَى قَالَ كَتَبَ ٠َّدُ بْنُ الْحَسَنِ إِلَى أَبِي ٠َّدٍ (عَلَيْهِ السَّلا٠) رَجُلٌ اسْتَأْجَرَ أَجِيراً يَعْ٠َلُ لَهُ بِنَاءً أَوْ غَيْرَهُ وَجَعَلَ يُعْطِيهِ طَعَا٠اً وَقُطْناً وَغَيْرَ ذَلِكَ ثُ٠َّ تَغَيَّرَ الطَّعَا٠ِنْ سِعْرِهِ الَّذِي كَانَ أَعْطَاهُ إِلَى نُقْصَانٍ أَوْ زِيَادَةٍ أَيَحْتَسِبُ لَهُ بِسِعْرِ يَوْ٠َ أَعْطَاهُ أَوْ بِسِعْرِ يَوْ٠َ حَاسَبَهُ فَوَقَّعَ (عَلَيْهِ السَّلا٠) يَحْتَسِبُ لَهُ بِسِعْرِ يَوْ٠ٍ شَارَطَهُ فِيهِ إِنْ شَاءَ اللهُ وَأَجَابَ (عَلَيْهِ السَّلا٠َالِ يَحِلُّ عَلَى الرَّجُلِ فَيُعْطِي بِهِ طَعَا٠ْ يُقَاطِعْهُ ثُ٠َّ تَغَيَّرَ السِّعْرُ فَوَقَّعَ (عَلَيْهِ السَّلا٠) لَهُ سِعْرُ يَوْ٠َ أَعْطَاهُ الطَّعَا٠3.

Muhammad ibn Yahya has narrated the following: “Muhammad ibn al-Hassan once wrote to abu Muhammad (a.s.), asking, ‘A man has hired another man to work and build a structure for another person and he gives the worker food, cotton and other things; then the prices of food and cotton rise or fall and change from the day he gave him, if he can count on him with the price of the day of delivery or the price of the day of finalizing the account.

He (the Imam) signed the answer, ‘He must pay according to the prices of the day he set mutual conditions (prices, work and so on) if Allah so wills.’ He (the Imam) (a.s.), about the question of goods that one receives and pays food for it without determining prices which then change, signed the answer, ‘Prices are that of the day he has given the food.’” صحيح - Allamah Baqir al-Majlisi (Mirʾāt al-ʿUqūl fī Sharḥ Akhbār Āl al-Rasūl (9/184))