Rosh Hashanah 6a:5ראש השנה ו׳ א:ה׳
§ The Sages taught in a baraita: The verse states: “That which is gone out of your lips you shall keep and do; as you have vowed as a gift to the Lord your God, which you have promised with your mouth” (Deuteronomy 23:24). “That which is gone out of your lips”; this is a positive mitzva. “You shall keep”; this is a prohibition, as the phrase “you shall keep” is a warning to keep oneself from sinning. “And do”; this is an admonition to the court to make you fulfill your vow. “As you have vowed”; this is referring to a vow-offering. “To the Lord your God”; this is referring to sin-offerings, guilt-offerings, burnt-offerings, and peace-offerings, teaching that one must keep his word and bring them. “As a gift”; this is understood in its literal sense to be referring to a gift-offering. “Which you have promised”; this is referring to objects consecrated for Temple maintenance. “With your mouth”; this is referring to vows of charity, to which one commits himself with his mouth.
Tosafot on Rosh Hashanah 6a:5:1תוספות על ראש השנה ו׳ א:ה׳:א׳
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Tosafot on Rosh Hashanah 6a:5:3תוספות על ראש השנה ו׳ א:ה׳:ג׳
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Isaiah 45:23ישעיהו מ״ה:כ״ג
By Myself have I sworn,
From My mouth has issued truth,
A word that shall not turn back:
To Me every knee shall bend,
Every tongue swear loyalty.
From My mouth has issued truth,
A word that shall not turn back:
To Me every knee shall bend,
Every tongue swear loyalty.
Bava Kamma 36b:16בבא קמא ל״ו ב:ט״ז
Following the verdict, that man who was slapped said to Rav Yosef: Since the fine is only half a dinar, I do not want it, as it is beneath me to collect such an amount. Instead, let him give it to the poor. Then he retracted his decision, and said to Rav Yosef: Let him give it to me, and I will go and sustain [ve’avri] myself with it.
Bava Kamma 36b:17בבא קמא ל״ו ב:י״ז
Rav Yosef said to him: Since you already committed to give it to charity, the poor have already acquired it and it now belongs to them. And although there are no poor people here to acquire it, we, the court, are the hand, i.e., the legal extension, of the poor. We represent them, as Rav Yehuda says that Shmuel says: Orphans
Tosafot on Bava Kamma 36b:17:1תוספות על בבא קמא ל״ו ב:י״ז:א׳
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