The Book of Transactions (Kitab Al-Buyu`)
Muslim :: Book 10 : Hadith 3723
Jabir b. 'Abdullah reported: We used to cultivate land on rent during the lifetime of Allah's Apostle (may peace be upon him) and we got a share out of the grain left in the ears after threshing them and something unspecified. Allah's Messenger (may peace be upon him) said: He who has land should cultivate it or let his brother till it, otherwise he should leave it.