Muwatta Imam Malik Book of I'tikaf in Ramadan, Hadith 7
Ziyad related to me from Malik from Ibn Shihab from Amra bint Abd ar-Rahman from A'isha that the Messenger of Allah ﷺ once wanted to do itikaf, and when he went off to the place where he wanted to do itikaf he found some tents there, which were A'isha's tent, Hafsa's tent, and Zaynab's tent. When he saw them he asked about them and someone told him that they were the tents of A'isha, Hafsa and Zaynab. The Messenger of Allah ﷺ said, "Do you think them devout?" Then he left, and did not do itikaf until Shawwal, when he then did it for ten days.
حَدَّثَنِي زِيَادٌ، عَنْ مَالِكٍ، عَنِ ابْنِ شِهَابٍ، عَنْ عَمْرَةَ بِنْتِ عَبْدِ الرَّحْمَنِ، عَنْ عَائِشَةَ، أَنَّ رَسُولَ اللَّهِ ﷺ أَرَادَ أَنْ يَعْتَكِفَ فَلَمَّا انْصَرَفَ إِلَى الْمَكَانِ الَّذِي أَرَادَ أَنْ يَعْتَكِفَ فِيهِ وَجَدَ أَخْبِيَةً خِبَاءَ عَائِشَةَ وَخِبَاءَ حَفْصَةَ وَخِبَاءَ زَيْنَبَ فَلَمَّا رَآهَا سَأَلَ عَنْهَا فَقِيلَ لَهُ هَذَا خِبَاءُ عَائِشَةَ وَحَفْصَةَ وَزَيْنَبَ . فَقَالَ رَسُولُ اللَّهِ ﷺ " آلْبِرَّ تَقُولُونَ بِهِنَّ " . ثُمَّ انْصَرَفَ فَلَمْ يَعْتَكِفْ حَتَّى اعْتَكَفَ عَشْرًا مِنْ شَوَّالٍ .