Is the mortgaging (Rahn) of a Mudabbir (a slave willed to be manumitted upon the master's death) valid?

Primary text

The mortgaging of a Mudabbir is valid, according to the apparent view of the Madhhab. This validity is predicated upon the permissibility of selling the Mudabbir. The rationale is that the contract is intended to satisfy a right from the pledged object, analogous to leaseholding (Ijarah). Furthermore, the condition attached to the manumission of the Mudabbir does not prevent the realization of the right secured by the mortgage, unlike a condition that matures before the debt becomes due. In the case of a Mudabbir, the debt takes precedence over the manumission stipulation, meaning the debt's claim prevents the manumission from taking effect prematurely, thus ensuring the purpose of the mortgage is achieved.