What do we learn from "Al Titen Es Picha Lachati Es Besarecha
Shevu'os 39a: Regarding all other transgressions, Hashem punishes (only) the sinner. Regarding swearing falsely, He punishes his family as well. "Besarecha" refers to his family. Metzudas Tziyon - children are called Besarecha - "v'Hayu l'Vasar Echad" (Bereishis 3:24).
Shabbos 32b, Metzudas David: Minors die due to vows of their parents. The handiwork of man ("Ma'aseh Yadecha") is his children. Metzudas Tziyon - Lachati is to decrease, like "v'Lo Yachati" (Shoftim 20:16).
Rav Sadya Gaon: Do not cause your mouth to be a reason to condemn you.
Rashi: Punishment for vows is imposed on your children.
Ibn Ezra: Why should your mouth bring sin and evil on your body, if you will not pay what you vowed with your mouth?
Rashbam: If you will say many words in front of Him, this will make you sin, for anyone who increases words, he brings sin (Avos 1:17). "Lachati" is like Lehachati (to make sin). The deeds are attributed to the hands, for they are the primary doers.
Ri Kara: Do not pledge mucht Tzedakah in public, and not pay.
Seforno: Even if you intend to pay, don't let 1 your lips express it in a way that can lead to sin, if you will not be able to pay, or transgress Me'ilah (benefit from) Hekdesh. The good deed is Nedavah (without Achrayus), like it says that no one ever transgressed Me'ilah with Hillel's Korban (Pesachim 66b; he was Makdish it shortly before offering it).
Metzudas Tziyon: Titen is to abandon (not guard), like "v'Lo Nasan Sichon" (Bamidbar 21:23).
Why does it say "Al Tomar Lifnei ha'Mal'ach Shegagah Hi [Lamah Yiktzof ha'Elokim Al Kolecha]"?
Rav Sadya Gaon: Do not tell the Shali'ach that you erred. Rashi - the Shali'ach (Ri Kara - of the Tzibur 1 ) comes to demand payment of the Tzedakah that you pledged b'Rabim. Do not tell him that you erred when you pledged - you thought that you are able to pay.
Ibn Ezra: Hashem appointed an angel to write all man's words. Do not tell him that your vow was a mistake!
Rashbam: After you increased words, do not say in front of Hashem that it is Shegagah due to your excess words. All your thoughts are revealed in front of Him. Why should He be angry about your voice (many words)?
Ri Kara: How wretched is this one - for a light matter like this, a mere voice without an action, he ruins his deeds! Ba'alei Batim lose their property due to pledging Tzedakah in public, and not payin (Sukah 29a-b).
Seforno: Do not tell the Chacham who comes to permit the vow that it was mistake - the heart was unlike the mouth, like often happens when one elaborates words. Hashem will be angry if you jest with Him like with a person, to vow without intent!
Metzudas David: A person's deeds are blessed due to Tzedakah. Therefore, it is proper that his deeds be destroyed when he vows Tzedakah in public, and not pay.
Erech Apayim 1(27): In the world to come, people are punished for Aveiros that they did not do. It seems to them that the angel erred. Really, it is because he spoke Leshon ha'Ra about Ploni, so he received Ploni's punishment and Ploni received his reward.
Metzudas David: The Gizbar of Hekdesh. (Presumably, he means the Gabai Tzedakah. Rishonim say that nowadays, 'Hekdesh' refers to Tzedakah. I did not find that real Hekdesh is called Tzedakah. - PF)
What is "Al Kolecha"?
Rashi: It is due to your voice.
What do we learn from "v'Chibel Es Ma'aseh Yadecha"?
Rashi, from Shocher Tov 52:1: Mitzvos that you already did, and you lost them 1 .
Ibn Ezra #1: Chibel is destroying, like "Mechabelim Keramim" (Shir ha'Shirim 2:15).
Ibn Ezra #2: Sometimes it is an expression of birth - "Yechabel Aven
Sotah 21a: An Aveirah can extinguish a Mitzvah, but not Torah. Rashi (21a) - it does not cancel the Mitzvah's protection from punishments, rather, receiving reward for it in the future.
Magihah (in Toras Chayim): Chibel is being tied with ropes. It has the same grammatical form as Itar; both are adjectives.
