Sahih Bukhari Volume 9, Book 90, Hadith 6959

حَدَّثَنِي إِسْحَاقُ، حَدَّثَنَا عَبْدُ الرَّزَّاقِ، حَدَّثَنَا مَعْمَرٌ، عَنْ هَمَّامٍ، عَنْ أَبِي هُرَيْرَةَ ـ رضى الله عنه ـ قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ يَكُونُ كَنْزُ أَحَدِكُمْ يَوْمَ الْقِيَامَةِ شُجَاعًا أَقْرَعَ، يَفِرُّ مِنْهُ صَاحِبُهُ فَيَطْلُبُهُ وَيَقُولُ أَنَا كَنْزُكَ‏.‏ قَالَ وَاللَّهِ لَنْ يَزَالَ يَطْلُبُهُ حَتَّى يَبْسُطَ يَدَهُ فَيُلْقِمَهَا فَاهُ ‏"‏‏

Narrated By Abu Huraira : Allah's Apostle said, "On the Day of Resurrection the Kanz (Treasure or wealth of which, Zakat has not been paid) of anyone of you will appear in the shape of a huge bald headed poisonous male snake and its owner will run away from it, but it will follow him and say, 'I am your Kanz.'" The Prophet added, "By Allah, that snake will keep on following him until he stretches out his hand and let the snake swallow it."