Sahih Muslim 2312 a
Musa b. Anas reported on the authority of his father:
It never happened that Allah's Messenger (ﷺ) was asked anything for the sake of Islam and he did not give that. There came to him a person and he gave him a large flock (of sheep and goats) and he went back to his people and said: My people, embrace Islam, for Muhammad gives so much charity as if he has no fear of want.
وَحَدَّثَنَا عَاصِمُ بْنُ النَّضْرِ التَّيْمِيُّ، حَدَّثَنَا خَالِدٌ، - يَعْنِي ابْنَ الْحَارِثِ - حَدَّثَنَا حُمَيْدٌ،
 عَنْ مُوسَى بْنِ أَنَسٍ، عَنْ أَبِيهِ، قَالَ مَا سُئِلَ رَسُولُ اللَّهِ صلى الله عليه وسلم عَلَى الإِسْلاَمِ
 شَيْئًا إِلاَّ أَعْطَاهُ - قَالَ - فَجَاءَهُ رَجُلٌ فَأَعْطَاهُ غَنَمًا بَيْنَ جَبَلَيْنِ فَرَجَعَ إِلَى قَوْمِهِ فَقَالَ
 يَا قَوْمِ أَسْلِمُوا فَإِنَّ مُحَمَّدًا يُعْطِي عَطَاءً لاَ يَخْشَى الْفَاقَةَ ‏.‏