[If one says:] “Konam, my marrying So-and-so the ugly,” and, in fact, she is good looking; “dark,” and she is fair; “short,” and she is tall —- he is permitted her. [This is] not because she was ugly and became good looking, or dark and became fair, or short and became tall, but because the neder was an error.  It happened once that someone made a neder prohibiting benefit from his sister's daughter, and they brought her to R' Yishmael's house, and made her beautiful. R' Yishmael said to him: “My son, regarding this woman did you vow?” He said to him: “No.” Thereupon, R' Yishmael permitted [her]. At that time R' Yishmael wept and said: “The daughters of Israel are beautiful, but poverty makes them ugly.”  When R' Yishmael died, the daughters of Israel raised a lament, saying: “Daughters of Israel, weep over R' Yishmael.” And so, too, it says about Saul (II Samuel 1:24): Daughters of Israel, weep over Saul.

A naarah who is betrothed —- her father and her husband revoke her nedarim. [If] the father revoked [a neder], but the husband did not revoke [it, or if] the husband revoked [it], but the father did not revoke [it], it is revoked; certainly [this is so] if one of them confirmed [the neder].