Is it permissible to condition the validity of a wife's revocation upon a condition?

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Conditioning the revocation upon a condition is not valid because it constitutes permitting access to a desired private part (farj), which is analogous to marriage. Therefore, saying, "I revoke you if you wish," or "Every time I divorce you, I have revoked you," is invalid. Furthermore, it implies revocation before ownership of the right of revocation is established, similar to divorce before marriage. Saying, "If your father arrives, I have revoked you," is also invalid because it is a condition.