What is the ruling if an option (*khiyar*) is stipulated in a contract of surety (*kafaalah*)?
Chapter on Guarantee (Daman)
Al-Mughni
Book of Assignment (Transfer of Debt)
Primary text
If an option is stipulated in a contract of surety, the surety contract becomes void (*tabtil*). This is the position of Al-Shafi'i because stipulating the option contradicts the essence (*muqtada*) of the contract, rendering it invalid, similar to stipulating that the surety shall not pay what the principal debtor owes. The essence of guarantee and surety is the obligation (*luzum*) of what is guaranteed or for which surety is given, and the option negates this requirement.
Supporting text
An alternative possibility is that the stipulation itself is voided while the surety contract remains valid, analogous to void stipulations in a sale contract.