Sahih Bukhari Volume 6, Book 65, Hadith 4671

حَدَّثَنِى إِسْحَاقُ بْنُ إِبْرَاهِيمَ، قَالَ قُلْتُ لأَبِي أُسَامَةَ أَحَدَّثَكُمْ زَائِدَةُ عَنْ سُلَيْمَانَ عَنْ شَقِيقٍ عَنْ أَبِي مَسْعُودٍ الأَنْصَارِيِّ قَالَ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم يَأْمُرُ بِالصَّدَقَةِ، فَيَحْتَالُ أَحَدُنَا حَتَّى يَجِيءَ بِالْمُدِّ، وَإِنَّ لأَحَدِهِمِ الْيَوْمَ مِائَةَ أَلْفٍ‏.‏ كَأَنَّهُ يُعَرِّضُ بِنَفْسِهِ‏.‏

Narrated By Shaqiq : Abu Mas'ud Al-Ansari said, "Allah's Apostle, used to order us to give alms. So one of us would exert himself to earn one Mud (special measure of wheat or dates, etc.,) to give in charity; while today one of us may have one hundred thousand." Shaqiq said: As if Abu Masud referred to himself.