Full Sharh — An-Nawawi's Forty Hadith 5
عَنْ أُمِّ الْمُؤْمِنِينَ أُمِّ عَبْدِ اللَّهِ عَائِشَةَ رَضِيَ اللَّهُ عَنْهَا، قَالَتْ: قَالَ: رَسُولُ اللَّهِ صلى الله عليه و سلم مَنْ أَحْدَثَ فِي أَمْرِنَا هَذَا مَا لَيْسَ مِنْهُ فَهُوَ رَدٌّ [رَوَاهُ الْبُخَارِيُّ] ،[وَمُسْلِمٌ] وَفِي رِوَايَةٍ لِمُسْلِمٍ: مَنْ عَمِلَ عَمَلًا لَيْسَ عَلَيْهِ أَمْرُنَا فَهُوَ رَدٌّ
English Translation
On the authority of the mother of the faithful, Aisha (ra), who said: The Messenger of Allah (ﷺ) said, “He who innovates something in this matter of ours (i.e., Islam) that is not of it will have it rejected (by Allah).” [Bukhari & Muslim] In another version in Muslim it reads: “He who does an act which we have not commanded, will have it rejected (by Allah).”
Source
An-Nawawi's Forty Hadith(الأربعون النووية)
Forty Hadith of an-Nawawi
Hadith Number
5