صحيح ابن خزيمه
Sahih Ibn Khuzaymah
جماع أبواب سنن السواك وفضائلهChapters on Siwak and its Virtues
Subchapter
Hadith Q134
وَإِنَّمَا بَدَأْنَا بِذِكْرِ السِّوَاكِ قَبْلَ صِفَةِ الْوُضُوءِ لِبَدْءِ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ بِهِ قَبْلَ الْوُضُوءِ عِنْدَ دُخُولِ مَنْزِلِهِ.
We have begun with the mention of the miswak, before describing the manner of ablution, because the Noble Prophet (peace be upon him) would begin with the miswak before performing ablution when entering his house.
