Keep your word when making transactions or agreements with others; Be honest and trustworthy; Fulfill your promises even if it means giving something valuable in return; Strive for ethical trading/exchange/transaction

This hadith speaks of the importance of trading and exchanging goods in an ethical manner. It is narrated that Allah's Messenger (PBUH) bought grain from a Jew for a specified time and gave him an iron coat-of-mail as a pledge. This shows us that it is important to keep our word when making transactions or agreements with others. We should always strive to fulfill our promises even if it means giving something valuable in return for the promise we make. Furthermore, this hadith also teaches us about the importance of trustworthiness when dealing with others in business matters. We should always ensure that we are honest and trustworthy so that people can rely on us when making transactions or agreements with them.