(53) باب قَوْلِهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «لاَ تَزَالُ طَائِفَةٌ مِنْ أُمَّتِي ظَاهِرِينَ عَلَى الْحَقِّ لاَ يَضُرُّهُمْ مَنْ خَالَفَهُمْ»
It has been related by, Yazid b. al-Asamm that he heard Mu'awiya b. Abu Sfyan quote a tradition from the Prophet (ﷺ) which he related from the Prophet (mail peace he upon him) -and he did not hear him quote from the Prophet (masy peace be upon him) any tradition other than this in the course of his sermon from the pulpit-that whom Allah wants to do a favour, He grants him an understanding of religion. A group of people from the Muslims will remain on the Right Path and continue until the Day of Judgment to triumph over those who oppose them.
Reference: Sahih Muslim 1037 d
In-book reference: Book 33, Hadith 251
USC-MSA web (English) reference(deprecated numbering scheme): Book 20, Hadith 4720