4. “He who abandons fasting during a day of Ramadaan without a valid excuse, or illness – then even if he were to fast for ever it would not make up for it.”
This hadeeth is quoted in disconnected form by al-Bukhaaree in his Saheeh (Fathul-Baaree. 4/160) without an isnaad. It is connected by Ibn Khuzaimah in his Saheeh (No. 1987), at-Tirmidhee (No.723) Aboo Daawood (No.2397). lbn Maajah (No. 1672), an-Nasaa’ee in al-Kubraa as occurs in Tahfatul Ashraaf (10/373), al-Baihaqee (4/228) and Ibn -Iajr in Taghleequt-To’leeq (3/170) by way of Abul-Mutawwas: from his father: from Aboo Hurairah.
Ibn Hajr says in Fathul-Baaree (4/161): “They disagree greatly in their narration from Habeeb ibn Abee Thaabit, it has three weaknesses: (i) contradiction of its narrators, (ii) the condition of Abul-Mutawwas is unknown, (ii) doubt about whether his father met Aboo Hurairah or not.”
Ibn Khuzaimah says after reporting it: “If the narration is authentic, since I do not know Abul Mutawwas or his father.” So this hadeeth is also weak.
These are four ahaadeeth which have been declared weak and unreliable by the scholars, yet we still hear them and see them every day in the blessed month of Ramadaan in particular, and at other times. It is apparent that some of these ahadeeth contain parts whose meaning is correct and established in our Sharee’ah in the Book or the Sunnah. However, this on its own does not allow us to attribute to Allah’s Messenger (sallalalhu alaihi wa-sallam) that which is not established authentically from him, particularly since this Ummah alone – to the exception of all previous nations has been particularized by Allaah, the One free of all imperfections, with the use of isnaads (chains of narration). Through them we can ascertain what is acceptable and what has been invented, and what is authentic (saheeh) from that which is not. It is a very precise branch of knowledge, and he indeed spoke well who described it as: “The study of what is narrated and the measure for the authenticity of narrations.”
“Fasting in Ramadaan as observed by the Prophet.” Shaikh Saleem al-Hilaalee and Shaikh Alee Hassan. AbdurRahman.org