And this is indicated by the words of Allah Most High:

“Prescribed for you is retribution for those killed: the free for the free, the slave for the slave, and the female for the female.”

More than one of the early Muslims said: This verse was revealed concerning two Arab tribes that had fought one another. Allah Most High commanded that their slain be set against one another: a free person from one tribe against a free person from the other, a slave against a slave, and a female against a female.

Then He said:

“But if anyone receives any pardon from his brother, then the claim should be pursued fairly and payment made to him graciously.”

That is, if either party is owed a balance by the other, the latter should pay it to them fairly, and the other party should seek it from them with kindness. Pursuing the claim means demanding payment, as the Prophet, may Allah bless him and grant him peace, said:

“Delay in payment by someone able to pay is injustice. If any of you is referred for payment to a solvent person, let him accept the referral.”

This is because, among groups with the strength to resist, whose members assist one another in fighting, liability rests, according to the majority of scholars, both upon those who directly engage in fighting, seizure, and destruction, and upon the supporters who assist them. Hence, according to the majority’s position, both the supporting accomplice and the direct perpetrator among highway robbers are subject to execution. Umar ibn al-Khattāb, may Allah be pleased with him, executed the highwaymen’s lookout—the man who watched the road for them.

Thus, those who cooperate in wrongdoing and aggression must face penalties, including liability for compensation and other sanctions. For this reason, the generality of jurists have said that, when two groups fight out of factional loyalty and rivalry for leadership, each group is liable for the losses it inflicts on the other in respect of