Is borrowing with usury to cover marriage expenses and life necessities considered a sin, and what are the implications for the children if the father does not repay the amount? And is the father taking books and other things from the grandfather's estate without the knowledge of the heirs considered theft? And what should be done if it is difficult to return these items due to the large number of heirs and the damage of some of them?

The question points to three matters: the father borrowing from the bank, the books, tapes, and odds and ends the father brought after the grandfather's estate was distributed, and what the questioner should do regarding these matters.

First point: It is not permissible for a Muslim to earn from unlawful means, as lawful earnings are a condition for prayers to be answered and for entering Paradise. If the bank is usurious, the questioner should advise his father to repent from this act and not return to it in the future. Repentance is not about getting rid of usurious money, but about resolving not to return to the sin.

Second point: The default for people is innocence. Therefore, it is not permissible to harbor ill suspicion towards the father regarding the furniture unless there is evidence of theft. The furniture might have been the mother's share, or some heirs might have given it to him, or the father might have purchased it through a lawful means.

Third point: If the questioner can spend on himself from lawful money outside of the father's money—assuming the bank is usurious—this is closer to piety and more cautious for religion. However, if there is no other way to spend except from the father's money, there is no harm in that.