1) A person should keep far away from oaths. Nevertheless, if he made an oath to do a certain act, he should not ask a wise man to repeal it. Instead, he should fulfil it. (In this way there is a distinction between an oath (where one promises to do something) and a vow (where one forbids an object for oneself) for when concerning a vow, it is better to repeal it than to fulfil it.) This is true even if it causes him pain, as it says, “One who swears to hurt himself and does not change his mind… One who does this will never be moved!” (Kitzur Shulchan Aruch 67).
2) One may not repeal an oath unless there are extenuating circumstances. The laws of how to repeal an oath are identical to those of repealing a vow, and must take place before three learned men, of whom at least one is an expert in the laws of oaths. (ibid).