(a) If I say "I promise to do ......" like something trivial like you promise your wife for example to pick the kids from school.
Is that formulation considered an oath or a vow? Does one have to go get a beis din to resolve such a thing, even if it is so trivial
(b) Based on the concept of a oath, neder for example would it be considered a false oath if an ashkenazi promised to eat say rice on peseach, because for him that is forbidden, would that have to be annuled or did it never take effect for him.
Rael Levinsohn, Sydney, Australia
(a) "I promise" is an affirmation, but not a Neder or Shevu'ah. It does not mean "I swear." However, one must keep his word even if it is not considered a Neder; it is forbidden to lie whether it involves a Neder or not.
(b) A Minhag (such as not eating rice on Pesach) is equivalent to a Rabbinic ordinance, with regard to Shevu'os. A Shevu'ah does not take effect if it involves the transgression of a Torah prohibition, but it does take effect if it involves the transgression a Rabbinic prohibition. Of course, the Shevu'ah does not permit the transgression of the Minhag. However, it does require one to have the Shevu'ah permitted by Beis Din so that one may keep the Minhag.
(1) The Maharsha, citing the Medrash Rabah, learns that Yiftach's Neder was not effective and did not therefore need to be annulled. However, he concludes from the Targum Yonasan that Rashi cites which talks about Yiftach not having the Neder nullified by Pinchas, it would appear otherwsise, and he has no ansawer to that. I thought that perhaps Yiftach and Pinchas erred in that, in reality, the Neder was not effective only since they thought that it was, they should at least have made a point of annuling it, and it is because they were both too proud to do so, that Hashem was angry with them.
(2) The Rav you asked presumably quoted you the ruling of the Shulchan Aruch (Y.D. 239:6), who specifically states that if somebody swears to transgress a Lo Sa'aseh, even if it is only de'Rabbanan, the Shevu'ah does not take effect. The Ba'er Heitev however, cites the Shach, who proves that we cannot take this ruling at surface value, and concludes that even if, strictly speaking, the ruling is correct, one nevertheless requests of the Noder to have his Neder annulled.
(3) Generally speaking, a Shevu'ah must be expressed. One that is made by thoughts alone is not considered a Shevu'ah, and that obviously applies in a case where a person makes a Shevu'ah using an incorrect Lashon, even though he has in mind the correct one. This is based on the principle 'Devarim she'be'Lev Einam Devarim'.
(4) Your question is precisely where the nations went wrong. Hashem's word is eternally sacrosanct (particularly one that He expressed for the good). That is why He will never abandon us, and that is why Eretz Yisrael is eternally ours.
The Gemara in Sanhedrin 105a, commenting on a Pasuk in Yechezkel, explains how, in reply to Yisrael's claim that, like a slave who has been set free, they were no longer obligated to serve Hashem, the latter replied and asked them to produce the Get Shichrur (the document of freedom) in support of their claim, and that since no such document existed, Hashem would have to use extremely harsh measures to force them to re-accept Him as King. The reason for that is because, even when Yisrael abrogates the covenant that they made with Hashem, He will never abrogate His side of the agreement, in which case He has no option (Kevayachol) other than to force their hand to revert to the original agreement.
To further prove my point, the Gemara in Berachos (32a) interprets the words in Shemos 32:11 "Vayechal Moshe" to mean that Moshe annulled the Neder that Hashem had made to destroy Klal Yisrael, before going on to pray on their behalf.
be'Virchas Kol Tuv