He was asked—may Allah have mercy on him:

A man was owed a debt by someone. He found the debtor’s son riding a mare and took the mare from him. The debtor came to the man holding the mare, and the creditor demanded repayment. The debtor said, “Keep this mare with you until I repay your debt.”

The creditor replied, “You owe me silver, not a mare. This is a living creature, and life and death are in the hands of Allah, glorified and exalted be He.”

The debtor said, “May Allah absolve you of liability for this silver. Whatever happens, I shall be responsible.”

The mare remained with the creditor for several days. He fed and watered her but did not ride her. Then, by Allah’s decree and ordainment, she miscarried a dead foal, which gave no cry at birth. Another man, other than the debtor, came forward, claiming that the mare belonged to him and making a claim for the miscarried foal.

The creditor said, “I do not know you, and you have no dealings with me. I will swear to you that I did not ride the mare, that no one rode her while she was with me, and that I did not strike her.”

Must either the creditor or the man who pledged the mare pay the value of the miscarried foal, or not? How much would the foal be worth?

He replied:

If you took possession of the mare from her owner without right, he is entitled to compensation for any diminution in her value, namely the difference between the valuations. If the person who took possession of her was a usurper acting unlawfully,