Making a sacrifice conditional on something

Question

If someone says: “If this cow becomes pregnant, I will keep (it); otherwise I will sacrifice it,” and for the present the cow has not become pregnant, can the cow now be sold and another cow or bull bought with its money and sacrificed, or not? May it be sold or not? Also, is this vow valid or not? The person mentioned is well-off.

Answer

The words mentioned in the question admit two possibilities: one is a promise to oneself, the other a vow (nadhr). If he did not intend a vow but intended a promise, then there is no vow at all, merely a promise, the fulfilment of which is not fard. If his interests so require, selling (the cow) is permissible, and in its place he may sacrifice another cow or the like.

Source: Fatawa Mahmudiyya

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