Sahih Muslim , Book 41, Hadith 6921 (USC-MSA) ⓘ
Abu Huraira reported Allah's Messenger as saying: The Euphrates would soon uncover a mountain of gold but he who is present there should not take anything from that.
حَدَّثَنَا سَهْلُ بْنُ عُثْمَانَ، حَدَّثَنَا عُقْبَةُ بْنُ خَالِدٍ، عَنْ عُبَيْدِ اللَّهِ، عَنْ أَبِي الزِّنَادِ، عَنْ عَبْدِ الرَّحْمَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " يُوشِكُ الْفُرَاتُ أَنْ يَحْسِرَ عَنْ جَبَلٍ مِنْ ذَهَبٍ فَمَنْ حَضَرَهُ فَلاَ يَأْخُذْ مِنْهُ شَيْئًا " .
also referenced under: Book 54, Hadith 41 (In-Book) & Hadith 2894 (Reference)