The Messenger of Allah ﷺ used to encourage people to pray during the nights of Ramadan without commanding them to do so as a binding obligation. He would say, "Whoever stands in prayer during Ramadan out of faith and seeking reward, his past sins will be forgiven."In another narration, he went out in the middle of the night to pray in the mosque, and the people prayed along with him. The narrator continued the hadith, including the following, He used to encourage them to pray during the nights of Ramadan without commanding them as a binding obligation, saying, "Whoever stands in prayer on Laylat al-Qadr out of faith and seeking reward, his past sins will be forgiven."The narrator said, "The Messenger of Allah ﷺ passed away while the matter remained as such."
إن رسول الله ﷺ كان يرغب الناس في قيام رمضان من غير أن يأمرهم بعزيمة أمر فيه، فيقول: من قام رمضان إيمانا واحتسابا غفر له ما تقدم من ذنبه. وفي رواية: خرج في جوف الليل يصلي في المسجد، وصلى بالناس وساق الحديث. وجاء فيه: وكان يرغبهم في قيام رمضان من غير أن يأمرهم بعزيمة ويقول: من قام ليلة القدر إيمانا واحتسابا غفر له ما تقدم من ذنبه. قال: فتوفي رسول الله ﷺ والأمر على ذلك.
Narrated by Nasai (2192, 2193, 2195), and Ibn Khuzayma (2207) and Ibn Hibban (2543) graded it sahih, through various routes from Zuhri, "Urwa bin Zubayr informed me, that Ayesha informed him," and then he related the hadith. Among those who also narrated it from Zuhri are Ibrahim bin Ismail bin Mujammi and Malik, both from Zuhri with this same chain. Daraqutni mentioned this in Ilal (3805), except that he said, "What is preserved from Zuhri is through Abu Salama and Humayd, from Abu Hurairah."I say, this is what appears most evident, given that the two Shaykhs (Bukhari and Muslim) relied on it, but this does not preclude Zuhri having multiple routes, one of them being through Urwa bin Zubayr, from Ayesha.As for what is narrated from Abdul-Rahman bin Awf, who said, the Messenger of Allah ﷺ said, "Allah has made the fasting of Ramadan obligatory upon you, and I have made its night prayer a sunnah for you, so whoever fasts it and prays in it out of faith and seeking reward emerges from his sins as on the day his mother bore him", this is daif.It was narrated by Nasai (2210) and Ibn Majah (1328) through Nadr bin Shayban, who said, "I said to Abu Salama bin Abdul-Rahman, tell me something you heard from your father, which your father heard from the Messenger of Allah ﷺ, with no one between your father and the Messenger of Allah ﷺ regarding the month of Ramadan." He said, "Yes. My father told me, saying, the Messenger of Allah ﷺ said" (and he related it), the wording being that of Nasai.Imam Ahmad narrated it (1660) through Nadr bin Shayban, similarly. Nasai also narrated it (2208) with the same chain, that the Messenger of Allah ﷺ mentioned the month of Ramadan and favored it above the other months, and said, "Whoever prays the night prayers of Ramadan out of faith and seeking reward emerges from his sins as on the day his mother bore him."Nasai said, "This is an error, and the correct version is, Abu Salama from Abu Hurairah." I say, meaning the hadith of the two Shaykhs mentioned shortly before. Bukhari likewise said, "It is not sahih, and the hadith of Zuhri and others from Abu Salama from Abu Hurairah is more sahih."The hadith revolves around Nadr bin Shayban, about whom Ibn Main said, "His hadith is worthless." Ibn Hibban mentioned him in Thiqat and said, "He was among those who made mistakes." Ibn Hajar took issue with this in Tahdheeb (10/438), saying, "If he erred in his hadith and has no other hadith besides it, then there is no sense in mentioning him among the trustworthy narrators, unless it is said that he himself is truthful and merely erred in the name of the companion, in which case it would make sense. But this is countered by the fact that in some of the routes from him it is stated, 'I met Abu Salama and said to him, tell me a hadith you heard from your father, which your father heard from the Prophet ﷺ.' Abu Salama said, 'My father told me,' and related it. A group of the scholars have firmly stated that Abu Salama's hearing from his father was not established as sahih, so on this basis the weakening of Nadr is settled. Ibn Kharrash said that he is not known except through this hadith. Daraqutni also found fault with it on account of the hadith of Abu Salama from Abu Hurairah." That is the end of what the Hafiz (Ibn Hajar) said.I say, among those who firmly stated that he did not hear from his father are Ali bin Madini, Ahmad, Ibn Main, Bukhari, Abu Hatim, Yaqub bin Shayba, and Abu Dawud. Ahmad said, "He died while still young."