The Prophet (ﷺ) came to Medina and the people used to pay in advance the prices of fruits to be delivered within two to three years. The Prophet (ﷺ) said (to them), "Buy fruits by paying their prices in advance on condition that the fruits are to be delivered to you according to a fixed specified measure within a fixed specified period." Ibn Najih said, " ... by specified measure and specified weight."
Sahih al-Bukhari Book 35, Hadith 14
← Previous Hadith We argued at Ibrahim's dwelling place about mortgaging in Salam. He said, "Aisha said, 'The Prophet (ﷺ) bought some foodstuff from a Jew on credit and the payment was to be made by a definite period, and he mortgaged his iron armor to him."

Sahih al-Bukhari Book 35, Hadith 13 Next Hadith → Abu Burda and `Abdullah bin Shaddad sent me to `Abdur Rahman bin Abza and `Abdullah bin Abi `Aufa to ask them about the Salaf (Salam). They said, "We used to get war booty while we were with Allah's Messenger (ﷺ) and when the peasants of Sham came to us we used to pay them in advance for wheat, barley, and oil to be delivered within a fixed period." I asked them, "Did the peasants own standing crops or not?" They replied, "We never asked them about it."

Sahih al-Bukhari Book 35, Hadith 15