Is it permissible for a husband to pay the expiation for an oath (feeding ten needy persons) on behalf of his wife, or is her fasting more effective in deterring her?

The expiation (kaffarah) is obligatory upon the wife alone, and she has the choice between feeding ten poor persons, clothing them, or emancipating a slave. If she is unable to do that, she must fast for three days. Fasting is not sufficient for her if she is able to feed, clothe, or emancipate a slave. There is no harm for the husband to undertake the expiation on behalf of his wife with her permission.