Regarding the Prophets Guidance in Voluntary Charity (Sadaqah at-Tatawwu)

He was the greatest of the people in giving charity with whatever was in his hands and he did not overestimate the value of anything which Allaah, tabaraak wa taalaa, gave him, nor did he underestimate it (ie. nothing in his possession was considered too much or too little by him to be given in charity). If anyone asked him for something, he would give it to him, whether it was little or much and his happiness and joy in giving was greater than that of the receiver! And when a person in deed submitted his case to him, he would give preference to his needs over his own, sometimes with his food and sometimes with his clothes.

His giving and charity were of different types: sometimes, it took the form of a gift, sometimes charity and sometimes a grant; and sometimes, he would buy something and then give it to the seller along with its price. At other times, he would borrow something and then return more than he had borrowed. He would accept a gift and in return, he would give something of greater value (narrated by al-Bukhaaree), out of his kindness and in order to express all diverse forms of charitable deeds to the utmost of his ability. His benevolence was expressed with his property, his actions and his words. He would give whatever he had, he would order the giving of charity and he would encourage it, so that if a miserly person saw him, his behavior would call upon him to be giving.

Anyone who associated with him could not help but be kind and generous. For this reason, he was the most open-hearted of people and the finest soul among them; for charity and righteous deeds have an amazing ability to open the heart- and this was in addition to this things by which Allaah had distinguished him, such as His opening his heart by the Message, its special characteristics and its consequences and the opening of his heart to compassion and the removal of Shaytaans portion (ie. influence) from it. Excerpt: Provisions for the Hereafter by Imaam ibn Qayyim al-Jawziyyah (rahimullaah)Pgs. 113-114