A loan should be written down with two witnesses if you expect repayment, since you will forget and Satan may cause confusion, though if you do not care about repayment it is okay.1, 2, 3, 4
Keeping excess change that a cashier gives you by mistake is eating other people's money dishonestly, and you should give the money back.1, 2, 3
It is no sin to seek commercial benefits during Hajj.1
In monetary transactions a man and a woman are not counted as two separate witnesses when they might marry, because spouses may influence each other and become like one witness.1, 2, 3
Islamic economy is a productive economy.1
Usury is any fixed percentage earned on deposited or loaned money, while earnings that fluctuate with investment profits and losses are not usury.1, 2
Whenever you lend money, you should write it down and have witnesses, because people tend to forget, and this is God's law to be followed.1, 2, 3
Usury involves a victim who is taken advantage of; wherever there is a victim there is sin, so ordinary bank interest, where both sides are happy, is not usury.1, 2, 3
Keeping money a cashier gives you by mistake, even if you think the cashier is an unbeliever, is wrong, and you must be honest with all people.1, 2, 3
In a loan the borrower dictates and writes down the terms, God gives the details of what to write, and two witnesses are added so there is no confusion.1, 2, 3
When you lend money and expect to be repaid, God tells you to write the loan down so neither side forgets the amount. If you do not care about repayment, it is okay not to.1, 2, 3