Is it permissible to borrow from a friend who is unaware that I have left my job, knowing that he lends based on his knowledge of my previous income and his assumption that I am able to repay the debt from my salary?

If a person needs to borrow money, there is no harm in it. However, they should explain their situation to the lender if the amount is large and difficult to repay, so as not to deceive or mislead them when there is a delay or inability to pay. As for small amounts that are not difficult to repay, there is no need to explain the situation. Some scholars have stated that borrowing becomes impermissible (haram) if the borrower is unable to repay and does not inform the lender of this.