Sahih al-Bukhari 2083
Sahih al-Bukhari · Book 34: Sales and Trade · The Statement of Allah Ta'ala: "... Eat not Riba doubled and multiplied."
Narrated Abu Hurairah (ra):
حَدَّثَنَا آدَمُ ، حَدَّثَنَا ابْنُ أَبِي ذِئْبٍ ، حَدَّثَنَا سَعِيدٌ الْمَقْبُرِيُّ ، عَنْ أَبِي هُرَيْرَةَ ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " لَيَأْتِيَنَّ عَلَى النَّاسِ زَمَانٌ لاَ يُبَالِي الْمَرْءُ بِمَا أَخَذَ الْمَالَ، أَمِنْ حَلاَلٍ أَمْ مِنْ حَرَامٍ " .
The Prophet (ﷺ) said "Certainly a time will come when people will not bother to know from where they earned the money, by lawful means or unlawful means." (See Hadith no. 2050)