Sayyiduna Ali (may Allah be pleased with him) and Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) report this saying of the Prophet (peace and blessings be upon him): "A promise (made to someone regarding some kind of payment) is a debt."
Al-Tabarani recorded it in al-Mu'jam al-Awsat and al-Mu'jam al-Saghir, and in it he added these words from Sayyiduna Ali (may Allah be pleased with him) alone: "Woe to the one who makes a promise and then breaks it" - he said this three times. Its chain contains a narrator, Hamzah bin Dawud, whom al-Daraqutni (may Allah have mercy on him) declared da'if (weak).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب البيوع / 6833
Hadith Gradingمحدثین:إسناده ضعیف
Hadith Takhrij«اخرجه الطبراني فى المعجم الصغير (419) ، أخرجه المعجم الأوسط للطبراني برقم: 3538، 3537»