ENOfficial
Abu Huraira reported God’s messenger as saying, "If anyone repents before the sun rises in the west, God will forgive him." Muslim transmitted it.
Source: sunnah.com
Other translations
Arabic
وَعَنْ أَبِي هُرَيْرَةَ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «مَنْ تَابَ قَبْلَ أَنْ تَطْلُعَ الشَّمْسُ مِنْ مَغْرِبِهَا تَابَ الله عَلَيْهِ» . رَوَاهُ مُسلم
sunnah.com