Do your actions of lending money to your friends in a currency different from the repayment currency, and exchanging it at a specific rate, constitute a form of usury, and what is the ruling on your Hajj in this case, and what must you do to atone for this matter?

The fundamental principle regarding a loan is that it must be repaid in the same currency that was originally owed by the borrower. It is not permissible to agree, at the time of the loan, to repay it in a different currency, because this constitutes usury (riba). This is based on the Prophet Muhammad's (peace be upon him) saying: "Gold for gold, silver for silver, wheat for wheat, barley for barley, dates for dates, and salt for salt - like for like, equal for equal, hand to hand. If these types differ, then sell as you wish, provided it is hand to hand."

However, it is permissible for the lender and the borrower to agree, at the time of repayment, to settle the debt in a different currency, because exchanging what is owed after it becomes due is like exchanging what is in hand. It is obligatory to repent to Allah for stipulating repayment in a different currency.