Q 1: What is the meaning of the scholars' statement: "This Hadith is weak and not authentic yet it should be acted upon" and "This Hadith is authentic but it should not be acted upon''?

A: The meaning of the statement: "This Hadith is weak and not authentic yet it should be acted upon" is that a Hadith may be weak in terms of Matn (text of a Hadith) or Sanad (chain of narrators). In other words, one of its narrators may be weak regarding his memorization or Irsal (narrating a Hadith with no Companion of the Prophet in its chain of narration), or because of being a Mudallis (a Hadith narrator who provides misleading information about his shaykh or the chain of narration), or an unknown narrator, or because the Hadith may contain any such aspects of weakness. In this case, the weak Hadith itself cannot be considered as proof on its own. However, it can be acted upon if there are other similar narrations that are free from aspects of weakness or if there are authentic proofs from the Qur'an, authentically reported Sunnah (whatever is reported from the Prophet), the practices of the Sahabah (Companions of the Prophet), or Ijma` (consensus of scholars) with the same meaning or ruling conveyed in the weak Hadith. Only then can a weak Hadith be acted upon. An example of this is the Hadith related by Al-Tirmidhy in his book "Jami` Al-Tirmidhy" from Ibn `Abbas (may Allah be pleased with him and his father) that the Prophet (peace be upon him) said: Anyone who combines two Salahs (Prayers) without a valid excuse has committed one of the major sins. Reporting this Hadith directly from the Prophet (peace be upon him) is questionable. However, Al-Tirmidhy commented on it saying: "Scholars have agreed on acting upon this Hadith." This means that combining two Salahs without a legal excuse is prohibited and is considered one of the major sins because it was reported from some Sahabah such as `Umar (may Allah be pleased with him) and because Allah (Exalted be He) says: Then, there has succeeded them a posterity who have given up As-Salât (the prayers) [i.e. made their Salât (prayers) to be lost, either by not offering them or by not offering them perfectly or by not offering them in their proper fixed times] and have followed lusts. So they will be thrown in Hell. (Part No. 3; Page No. 193) And: So woe unto those performers of Salât (prayers) (hypocrites), Those who delay their Salât (prayer from their stated fixed times). Another example is the Hadith narrated on the authority of Abu Umamah Al-Bahily (may Allah be pleased with him) that the Messenger of Allah (peace be upon him) said: Water does not become impure by anything unless it is something that clearly changes its smell, taste, or color. (Related by Ibn Majah and others) According to the great scholars of Hadith, this is a weak Hadith, yet its ruling and meaning are authentic and are acted upon. Al-Nawawy said: "The Muhaddiths (Hadith scholars) agree that this Hadith is weak." This means it is the exception mentioned in the Hadith that is ranked as weak, not the basic meaning of the Hadith; because this basic meaning was confirmed to be authentic by the Hadith on the well of Buda`ah. Yet, the scholars have agreed on acting upon the ruling stated in the weak part of the narration. Ibn Al-Mundhir said: "Muslim scholars have unanimously agreed that if some impurity falls in water, no matter how little or much the water is, causing its smell, taste, or color to change, the water is considered impure water." Therefore, the Ijma` represents the proof that this water becomes impure if one of its characteristics changes; a proof that is not deduced from the exception mentioned in the Hadith.As for the saying: "This Hadith is authentic but it should not be acted upon," it means that this Hadith is either abrogated by an authentic Hadith that has been revealed after it or there is a conflict between this Hadith and a more authentic one and both cannot be acted upon together (Part No. 3; Page No. 194) or it is difficult to reconcile them through well-known means of reconciliation between conflicting proofs. In such cases, the scholars of Hadith prefer one Hadith to the other based on legal reasons, such as the fact that the Sahabah acted upon it, the multitude of its narrators, and so on. The disregarded Hadith is considered a Hadith Shadh (a Hadith narrated by a trustworthy narrator, not in line with the narration of other trustworthy narrators in terms of wording, chain of narrators, or both) because there is a more authentic one.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.