Is it permissible to issue a fictitious purchase invoice for a computer that has not been sold, in order to enable someone to obtain a financial advance designated for purchasing a computer?

If the lending institution stipulates the purchase of a computer, then its condition must not be violated, based on the Prophet's (peace be upon him) saying: "Muslims are bound by their conditions, except for a condition that makes a haram lawful or a halal unlawful," and his saying: "Whoever deceives is not of me."

Deception by submitting fictitious invoices to obtain the loan is forbidden, and aiding the deceiver by providing fictitious invoices is also forbidden, as it falls under cooperation in sin and aggression.