The Sufficient (Vol 7) · Hadith 785 (#Ḥadīth #14)
Chapter 7 | The Binding Consequence of Oath and Vows
14- أَحْمَدُ بْنُ مُحَمَّدٍ عَنِ ابْنِ فَضَّالٍ عَنِ ابْنِ بُكَيْرٍ عَنْ زُرَارَةَ عَنْ أَبِي جَعْفَرٍ قَالَ قُلْتُ لَهُ الرَّجُلُ يَحْلِفُ بِالأيْمَانِ الْمُغَلَّظَةِ أَنْ لا يَشْتَرِيَ لأهْلِهِ شَيْئاً قَالَ فَلْيَشْتَرِ لَهُمْ وَلَيْسَ عَلَيْهِ شَيْءٌ فِي يَمِينِهِ.
14. Ahmad ibn Muhammad has narrated from ibn Faddal from ibn Bukayr from Zurarah who has narrated the following: “I once asked abu Ja‘far , about the case of a man who takes an oath very seriously not to buy for his family. He (the Imam) said, ‘He must buy for them and he does not owe anything because of his oath.’”
Gradings are classical jarḥ-wa-taʿdīl, name-matched to a rijāl index (not individually re-verified).