ENOfficial
Abu Huraira reported the Prophet (ﷺ) as saying, "I am just a mercy which has been bestowed." Darimi and Baihaqi, in Shu'ab al-iman, transmitted it.
Source: sunnah.com
Other translations
Arabic
وَعَنْ أَبِي هُرَيْرَةَ عَنِ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ أَنَّهُ قَالَ: «إِنَّمَا أَنَا رَحْمَةٌ مُهْدَاةٌ» . رَوَاهُ الدَّارِمِيُّ وَالْبَيْهَقِيُّ فِي «شُعَبِ الْإِيمَانِ»
sunnah.com