Hadith 534
أَخْبَرَنَا مُحَمَّدُ بْنُ مَنْصُورٍ، قَالَ حَدَّثَنَا سُفْيَانُ، قَالَ حَدَّثَنَا أَبُو الزِّنَادِ، عَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " لَوْلاَ أَنْ أَشُقَّ عَلَى أُمَّتِي لأَمَرْتُهُمْ بِتَأْخِيرِ الْعِشَاءِ وَبِالسِّوَاكِ عِنْدَ كُلِّ صَلاَةٍ " .
It was narrated from Abu Hurairah that the Messenger of Allah (ﷺ) said:
"Were it not that I would impose too much difficulty on my Ummah, I would have commanded them to delay 'Isha' and to use the Siwak for every prayer."
Reference : Sunan an-Nasa'i 534
In-book reference : Book 6, Hadith 41