When does the obligation of payment for a deed of manumission (Kitabah) become due?

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The obligation for payment (Itā') stipulated in the contract of manumission becomes due immediately upon the manumission agreement itself, because Allah commanded giving from the wealth bestowed upon him, and when wealth is given, manumission occurs, thus payment is obligatory at that point. Ali, may Allah be pleased with him, stated that the contract is established on two installments, and the payment is due from the second installment. If the master dies before the payment is made, it becomes a debt against his estate, taking precedence over bequests (Wasaaya) because it is a debt. If the estate is insufficient to cover this debt and other debts, all creditors share proportionally according to their rights.