What is the ruling on obtaining housing finance (to purchase a home or for construction) from a usurious bank where the employee works, knowing that this financing has a simple interest rate of 4% annually, and the bank pays the value of the apartment directly to the seller in the case of purchase, or disburses installments to the employee for construction, and in the case of financing from an Islamic bank, the murabahah is higher?

Working in an interest-based bank is impermissible because it constitutes assisting with usury. The worker may be afflicted by the curse pronounced upon the devourer of usury, its giver, its scribe, and its two witnesses. Therefore, one must leave such work unless there is a necessity. As for purchasing through the bank in the form of a loan with an increase, it is forbidden, due to His Almighty's saying: "And if you repent, you may have your principal – [thus] you do not wrong, nor are you wronged" and "O you who have believed, fear Allah and give up what remains [due to you] of usury, if you should be believers." However, purchasing through murabahah (definition) is permissible because it is a legitimate trade.