Messenger of Allah ﷺ said, "Someone came to me from my Lord and gave me the news (or good tidings) that if any of my followers dies worshipping none (in any way) along with Allah, he will enter Paradise." I asked, "Even if he committed illegal sexual intercourse (adultery) and theft?" He replied, "Even if he committed illegal sexual intercourse (adultery) and theft." (Using translation from Bukhārī 1237)
عَنِ النَّبِيِّ ﷺ قَالَ بَشَّرَنِي جِبْرِيلُ أَنَّ مَنْ مَاتَ مِنْ أُمَّتِكَ لَا يُشْرِكُ بِاللهِ شَيْئًا دَخَلَ الْجَنَّةَ قُلْتُ لَهُ وَإِنْ زَنَى وَإِنْ سَرَقَ؟ قَالَ وَإِنْ زَنَى وَإِنْ سَرَقَ