Mukhtasar Muslim

Ma'dan bin Abi Talhah al-Ya'mari says: I met Thawban (may Allah be pleased with him), the freed slave of the Messenger of Allah (peace and blessings be upon him), and I said to him, "Tell me of an act by which Allah will admit me to Paradise," or he said, "Tell me of the deed which is most beloved to Allah." Upon hearing this, Thawban (may Allah be pleased with him) remained silent. Then I asked him again, but he remained silent. When I asked him a third time, he said, "I also asked the Messenger of Allah (peace and blessings be upon him) this question, and he said: 'Make frequent prostrations (sujood) to Allah, for you will not make a single prostration to Allah except that Allah will raise you one degree and remove from you one sin.'" Ma'dan said: Then I met Abu al-Darda (may Allah be pleased with him) and asked him the same question, and he gave the same answer as Thawban (may Allah be pleased with him) had given.