If the borrower has to pay interest. Interest such as expenses of the borrower and in return the lender receives interest Interest is the income of the lender as well.
If borrowers have to pay interest, it was considered to be expenses of the borrower and vice-versa in case of lenders has been the interest is income of the lender as well.
If the borrower has to pay the interest rate assumption is that of the borrower and, in turn, in case the loan is interest income interest, it is the loan as well.