(3) باب السَّلَمِ إِلَى مَنْ لَيْسَ عِنْدَهُ أَصْلٌ
Narrated Muhammad bin Al-Mujalid:
`Abdullah bin Shaddad and Abu Burda sent me to `Abdullah bin Abi `Aufa and told me to ask `Abdullah whether the people in the lifetime of the Prophet (ﷺ) used to pay in advance for wheat (to be delivered later). `Abdullah replied, "We used to pay in advance to the peasants of Sham for wheat, barley and olive oil of a known specified measure to be delivered in a specified period." I asked (him), "Was the price paid (in advance) to those who had the things to be delivered later?" `Abdullah bin `Aufa replied, "We did not use to ask them about that." Then they sent me to `Abdur Rahman bin Abza and I asked him. He replied, "The companions of the Prophet (ﷺ) used to practice Salam in the lifetime of the Prophet; and we did not use to ask them whether they had standing crops or not."
Reference: Sahih al-Bukhari 2244
In-book reference: Book 35, Hadith 7
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 3, Book 35, Hadith 447