Sunan Ibn Majah 3823
سنن ابن ماجه#3823SahihIt was narrated from Abu Hurairah that the Messenger :of Allah (saas) said: "Every deed of the son of Adam will be multiplied for him, between ten and seven hundred times for each merit. Allah said: 'Except for fasting, for it is for Me and I shall reward for it.'" (sahih)
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniSahih
Muhammad Fouad Abd al-BaqiSahih
Shuaib Al ArnautSahih
Zubair Ali ZaiSahih
In-book reference: 33:167