Aisha reported: If the Messenger of Allah, peace and blessings be upon him, took up a practice, he would be resolved to make it a habit. If the Prophet slept through his night prayer or he was ill, he would pray twelve cycles in the day.
Source: Ṣaḥīḥ Muslim 746
Grade: Sahih (authentic) according to Muslim
عَنْ عَائِشَةَ قَالَتْ كَانَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ إِذَا عَمِلَ عَمَلًا أَثْبَتَهُ وَكَانَ إِذَا نَامَ مِنْ اللَّيْلِ أَوْ مَرِضَ صَلَّى مِنْ النَّهَارِ ثِنْتَيْ عَشْرَةَ رَكْعَةً
746 صحيح مسلم كتاب صلاة المسافرين وقصرها باب جامع صلاة الليل ومن نام عنه أو مرض
