Sahih Muslim | Book 8 | Chapter 8

Narrated by 'Uqba b. Amir (Allah be pleased with him)
'Uqba b. Amir (Allah be pleased with him) reported Allah's Messenger (may peace be upon him) as saying: The most worthy condition which must be fulfilled is that which makes sexual intercourse lawful. In the narration transmitted by Ibn Muthanna (instead of the word "condition") it is "conditions".