Come and hear: R. Eliezer said to them. If where a man cannot annul his own vows, once he has vowed, he can nevertheless annul his own vows before making them; then where he can annul his wife's vows after she vowed, how much the more should he be able to annul them before she vows! Now, surely this means that his wife's [vows] are like his: just as his vows take no effect at all, so his wife's vows too would take no effect at all! — No: each is governed by its own laws. Come and hear: They answered R. Eliezer: If a mikweh, though it raises the unclean front their uncleanness, cannot nevertheless save the clean from becoming unclean; then a man, who cannot raise the unclean from their uncleanness, how much the more can he not save the clean from becoming unclean. This proves that they take no effect at all.