When can Da`if Hadiths be accepted as evidence?

Q 3: Is it true that Hadith Da‘if (a Hadith that fails to reach the status of Hasan i.e., Good Hadith due to a weakness in the chain of narration or one of the narrators) cannot be accepted as evidence except in supererogatory acts of worship? Should they be disregarded altogether in religious rulings?

A: Firstly: A weak Hadith can be used as evidence in support of supererogatory acts if it is not very weak and the acts are wholly righteous. Moreover, it can only be cited as evidence in determining the details of these acts. Secondly: the weak Hadith can be used in establishing rulings if it is supported by another sound Hadith that bears the same meaning, or there exists numerous narrations to the extent that it becomes well known. (Part No. 4; Page No. 370) In this case it will fall under the fourth category of the Hadith accepted as evidence, which is Al-Hasan Li Ghayrih (A Hadith is judged Good by virtue of another Hadith when its weakness is so slight that it can be raised through another chain to the level of the Good Hadith).May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.