2,843. A Man Who Imposes a Vow on His Wife

Hilchos Nedarim 13:13

Let’s say that a man makes a vow and he imposes the same vow on his wife, having decided to have her take this vow. If she responds with amen, he can’t annul her vow. If he made a vow and imposed it on her in the form of a question to see what she thought – such as if he asked her, “Do you want to be like me in this vow?” – then if she says amen, he can annul her vow.

Hilchos Nedarim 13:14

Pursuant to the previous halacha, let’s say a man declares himself a nazir and then he says to his wife, “And you’re one, too.” If she says amen, he can’t annul her vow. Now let’s say that he declares himself a nazir and he asks his wife, “Will you be a nazir like me?” If she answers amen, he can annul her vow. If he annuls her vow, his is likewise annulled, because it's as if he made his vow dependent on hers. If the woman said to her husband, “I’m a nazir; how about you?” and he answers amen, he can’t annul her vow. The same is true in all comparable cases.