What is the ruling when a master acknowledges receiving the *kitabah* (manumission contract) payment from a slave?

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If a master acknowledges receiving the payment for the slave's *kitabah*, the slave is manumitted, provided the master is one whose acknowledgement is legally valid. This acknowledgement holds true even if made during the master's terminal illness, as an acknowledgement made by a sick person in favor of a non-heir is accepted.