What should a man do who exploited the currency exchange rate difference with an amount of 7,0 dollars from a charitable organization's funds, then invested it in speculation, but the project failed and the money could not be recovered? Does he have to repay the amount to the same organization, or can he direct it to other charitable projects, knowing that he does not currently possess the amount and supports his relatives?

The exchange rate difference is considered part of the total money collected for the stated purposes. The man made a grave mistake by mismanaging the money that came into his possession, especially since some of it was allocated for orphans. Islamic law has warned against misappropriating an orphan's money. Allah Almighty says: "Indeed, those who devour the property of orphans unjustly are only consuming into their bellies fire. And they will be a-blazing in a Sazeer (blazing Fire)." There is no difference in sin between devouring an orphan's money and causing a loss of its benefit. He must repent and return all the money to the institution managing it, because he betrayed its trust, and "on the hand is what it took until it returns it." His personal circumstances do not change the ruling in any way.