fornication. Likewise, in all these cases, they did not dispute that no sin attaches to the person who eats, wears clothing, or has intercourse without knowing. Their disagreement concerns only liability for compensation, because such liability belongs to the justice required in matters of people’s rights and applies whether the act was deliberate or mistaken:

“It is not for a believer to kill another believer except by mistake. Whoever kills a believer by mistake must free a believing slave and pay blood money to the deceased’s family, unless they waive it as charity.”

Someone who kills a person by mistake incurs no sin and does not become an evildoer thereby, but must pay blood money. Likewise, someone who mistakenly destroys unlawfully seized property must compensate for it, although he incurs no sin. It is thus clear that there is no sin in the absence of knowledge.

Accordingly, it is undoubtedly permissible to transact with Muslims, Jews, and Christians concerning any property in their possession when neither evidence nor any indication establishes that it was unlawfully seized or taken into possession in a manner that makes transactions with its holder impermissible. I know of no disagreement among the imams concerning this.

It is well known that most people’s property falls into this category. Taking possession through outright wrongdoing does not confer ownership. As for property received under an invalid contract, such as usury, gambling, and the like, does taking possession confer ownership? The jurists hold three views:

The first is that it does confer ownership. This is the position of Abū Hanīfa.

The second is that it does not confer ownership. This is the position of al-Shāfiʿī and of Ahmad according to the well-known position