Sayyidina Abu Juhayfah narrated: Allah’s Messenger (SAW) established fraternal ties between Salman and Abu Darda. Once, Salman visited Abu Darda and observed Umm Darda in a hackneyed condition, so he asked, “What is wrong with you? Worn-out?” She Said, “Abu Darda has no worldly ambition.” When Abu Darda came, he served the meal to Salman and said, “I will not eat till you eat.” So, he ate. When it was night, Abu Darda stood ip in prayer but Salman said to him, “Sleep,” so he slept, but soon got up to pray. Salman said to him, “Sleep”, so he slept. When it was morning, Salman said to him. “Stand up, now.” So, he stood up and they offered salah and he said, “Indeed, your soul has a right over you, your Lord has a right over you, your guest has a right over you. So give every owner of right” They came to the Prophet and he related what had transpired to him and he said, “Salam has spoken the truth.”
[Bukhari 1968]