One who divorces his wife because of a bad reputation may not take [her] back; because of a neder, he may not take [her] back. R' Yehudah says: [If because of] any neder which was known to the public, he may not take [her] back, but [if because of a neder] not known to the public, he may take [her] back.  R' Meir says: [If he divorced her because of] any neder which requires the inquiry of a sage, he may not take [her] back, but [if because of a neder] which does not require the inquiry of a sage, he may take [her] back. Said R' Elazar: They prohibited this only because of the other. Said R' Yose bar Yehudah: It occurred in Sidon that one said to his wife: “Konam, if I do not divorce you,” and he divorced her, and the Sages allowed him to take her back, for the sake of the general good.