Musnad Ahmad 31:889

'Abd al-Razzaq narrated to us, Ma'mar informed me, from al-Zuhri, from 'Ata' ibn Yazid al-Laythi, from Abu Sa'id al-Khudri, who said: Some people from the Ansar came and asked him [the Prophet], so he gave them. He continued, and none of them would ask him for anything except that he gave it to them, until what he had was exhausted. When he had spent everything in his hand, he said to them: "Whatever good we have, we will not withhold it from you. Whoever seeks to be chaste, Allah will make him chaste; whoever seeks to be self-sufficient, Allah will make him self-sufficient; and whoever seeks to be patient, Allah will give him patience. And you will never be given a gift better and more vast than patience."