وَقَدْ بَلَغَنِي ، أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ أَرَادَ الْعُكُوفَ فِي رَمَضَانَ ، ثُمَّ رَجَعَ فَلَمْ يَعْتَكِفْ حَتَّى إِذَا ذَهَبَ رَمَضَانُ ، اعْتَكَفَ عَشْرًا مِنْ شَوَّالٍ
Malik, may Allah have mercy on him, said: It has reached me from the Messenger of Allah, peace and blessings be upon him, that he intended to perform i'tikaf, then he returned and did not perform i'tikaf until after Ramadan, and then he performed i'tikaf for ten days in Shawwal.