On the authority of Thawban, the freed slave of the Messenger of Allah, may Allah bless him and grant him peace: that when the Prophet, may Allah bless him and grant him peace, wanted to conclude his prayer, he would seek forgiveness three times, then say: "O Allah" — and he mentioned the meaning of the hadith of Aisha(1).

359 - Chapter on seeking forgiveness

1514 - Al-Nufayli narrated to us, Makhlad ibn Yazid narrated to us, Uthman ibn Waqid al-Umari narrated to us, on the authority of Abu Nusayrah, on the authority of a freed slave of Abu Bakr al-Siddiq, on the authority of Abu Bakr al-Siddiq who said: The Messenger of Allah, may Allah bless him and grant him peace, said: "The one who seeks forgiveness is not persistent in sin, even if he returns to it seventy times in a day."(2)

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(1) Its chain is authentic. Isa: he is Ibn Yunus al-Sabi'i, and al-Awza'i: he is Abd al-Rahman ibn Amr, and Abu Ammar: he is Shaddad ibn Abd Allah al-Qurashi, and Abu Asma': he is Amr ibn Mirthad.
It was also narrated by Muslim (591), Ibn Majah (928), al-Tirmidhi (300), and al-Nasa'i in "al-Kubra" (1261) and (9891) through various chains from al-Awza'i, with this chain.
It is in "Musnad Ahmad" (22365), and "Sahih Ibn Hibban" (2003).
See what precedes it.

(2) A good (hasan) hadith, as Ibn Kathir said in his "Tafsir." He said: The anonymity of the freed slave of Abu Bakr does no harm, because he is a major Tabi'i, and his attribution to Abu Bakr suffices. It was also deemed good by al-Zayla'i in "Takhrij Ahadith al-Kashshaf," Ibn Hajar and al-Ayni in their two commentaries on al-Bukhari, and Ibn Muflih in "al-Adab al-Shar'iyyah." Al-Nufayli: he is Abd Allah ibn Muhammad ibn Ali ibn Nufayl, and Abu Nusayrah: he is Muslim ibn Ubayd al-Wasiti.
It was also narrated by al-Tirmidhi (3875) via the route of Uthman ibn Waqid, with this chain. He said: This is a gharib hadith, and its chain is not strong. Ibn Kathir responded to him in "al-Tafsir" with the words we have mentioned above. =