The Messenger of Allah ﷺ used to observe spiritual retreat during the last ten days of Ramadan until Allah took him.
حدثنا عبد الرزاق حدثنا معمر عن الزهري عن عروة عن عائشة وعن ابن المسيب
أن رسول الله ﷺ كان يعتكف العشر الأواخر من رمضان حتى قبضه الله عز وجل
Its isnad is sahih. In reality it is two hadiths narrated by Maamar from Zuhri, one of them Zuhri from Urwa from Ayesha, and the second Zuhri from Ibn Musayab from Abu Hurairah. So these are two hadiths from two companions, with two chains, presented together as one hadith. Tirmidhi likewise narrated it, 2:38, by way of Abdul-Razzaq with this same chain, and said, the hadith of Abu Hurairah and Ayesha is hasan sahih.It will also come, from the hadith of Abu Hurairah and Ayesha, in the Musnad of Ayesha 6:169h, from Muhammad bin Bakr, from Ibn Jurayj, from Zuhri, with the two chains. Abdullah bin Ahmad said there, I heard my father say, this hadith is like this in the book of fasting, from Abu Hurairah and Ayesha, but in itikaf, from Ayesha alone.It will also come in her Musnad, 6:232h, from Abdul-Razzaq, from Maamar, from Zuhri, from Urwa, from Ayesha alone. It will also come in her Musnad, 6:168h, from Abdul-Razzaq and Ibn Bakr, both of them from Ibn Jurayj, from Ibn Shihab, from Saeed bin Musayab and Urwa together, from Ayesha alone.Mubarakpuri, the commentator on Tirmidhi, attributed this hadith, in the narration of Ayesha and Abu Hurairah, to the two Shaykhs (Bukhari and Muslim). I consider him mistaken in this, or careless, for I did not find it in this form in the Sahihayn, nor in the rest of the six books, from the hadith of Abu Hurairah. Rather, Bukhari narrated it, 4:235-236, and Muslim, 1:236, and Abu Dawud, 2462, all three of them by way of Layth, from Aqeel, from Zuhri, from Urwa, from Ayesha alone, and they added at the end, then his wives observed itikaf after him.This narration by way of Layth will also come in the Musnad of Ayesha, 2:96h. Hafiz has pointed to this narration of Maamar in Fath al-Bari, 4:236, while explaining the hadith of Ayesha, saying, Maamar added in it, from Ibn Shihab, from Saeed bin Musayab, from Abu Hurairah, but he did not mention who recorded it. It is, as you see, in the Musnad and in Tirmidhi. He should have mentioned that Ibn Jurayj likewise narrated it from Zuhri, as we have noted.Abu Hurairah has another hadith about itikaf, other than this hadith, and from a different route. Bukhari narrated it, 4:245, and Ibn Majah, 1769, by way of Abu Bakr bin Ayyash, from Abu Husayn, from Abu Salih, from Abu Hurairah. It is among the reports unique to Bukhari, which Muslim did not narrate in his Sahih. It will come by this route in the Musnad, 8416, 8674, 9201, and see what has preceded in the Musnad of Abdullah bin Umar, 6172.