Abu Darda was a trader in Madinah who converted from Judaism to Islam after hearing Muhammad's teachings. He was declared the brother of Salman the Persian and served as a judge in Syria during the caliph Uthman's reign.
Abu Darda's own preaching focused on the insignificance of worldly wealth and the minor details of life. According to him, this life was comparable to a loan.
It is said of Abu Darda that once a friend went to visit him at his home. On reaching there, the friend noticed, with grave concern, the appalling condition of Abu Darda's house. According to the friend, Abu Darda's house was shorter that the full height of a standing man. It was also as narrow as it was shot, and the household utilities were less than basic. When the friend inquired from Abu Darda why he lived in such dire conditions, Darda's response was: "Do not worry my friend, this is just my temporary shade. I am building a proper house some where, slowly putting good things deserving thereof." When, on another occasion, the friend went back and found the same deprived shade, he demanded to know why Abu Darda had not moved to his better house. It was then that Abu Darda revealed to him that the house he referred to was the Kabr (the grave). [Story adopted from Faza'il-E-A'amaal? (published by Altaf & Sons) or one of those other books by the "Ahl Jama". Please verify....citation necessary]
He also strongly advocated the acquisition of knowledge, saying, “None of you can be pious unless he is knowledgeable, and he cannot enjoy knowledge unless he applies it practically.” Abu Darda praised scholars of Islam greatly for their knowledge and application of it. He lauded both student and the teacher, saying they would receive equal reward.
Abu Darda also preached the importance of strength in relationships, saying, “ To admonish your brother is better than to lose him. Give your brother advice and be tender with him, but do not agree with his covetousness lest you should be like him.” The reference to brothers is generally interpreted to refer to the wider Muslim family, rather than immediate siblings.