https://torontodawah.com/why-did-the-prophet-do-itikaaf-for-20-days-in-his-last-year-and-repeat-the-quran-twice-in-his-last-year-if-he-didnt-know-when-he-would-die/
Why Did The Prophet Do Itikaaf For 20 Days In His Last Year And Repeat The Quran Twice In His Last Year If He Didn't Know When He Would Die