Shevuot 57
ואכל תאנים והפריש קרבן ואח"כ אכל ענבים לחודייהו הויא להו ענבים חצי שיעור ואחצי שיעור לא מיחייב קרבן הכא נמי כגון דאמר שבועה שלא אוכל עשר וחזר ואמר שבועה שלא אוכל תשע ואכל תשע והפריש קרבן ואח"כ אכל עשירית הויא לה עשירית חצי שיעור ואחצי שיעור לא מיחייב:
<br> and he ate figs, and set apart the offering; and then he ate grapes alone, the grapes are then only half the quantity, and for half the quantity he is not liable. So here also, if he said: 'I swear I shall not eat ten [figs],' and then he said, 'I swear I shall not eat nine [figs],' and he ate nine, and set apart the offering, and then he ate a tenth [fig], the tenth is then only half the quantity, and for half the quantity he is not liable. <br>
<big><strong>מתני׳</strong></big> איזו היא שבועת שוא נשבע לשנות את הידוע לאדם אמר על העמוד של אבן שהוא של זהב ועל האיש שהוא אשה ועל האשה שהיא איש
MISHNAH. WHAT IS A VAIN OATH? IF HE SWORE THAT WHICH IS CONTRARY TO THE FACTS KNOWN TO MAN, SAYING OF A PILLAR OF STONE THAT IT IS OF GOLD; OR OF A MAN THAT HE IS A WOMAN; OR OF A WOMAN THAT SHE IS A MAN; IF HE SWORE CONCERNING A THING WHICH IS IMPOSSIBLE, [AS E.G., 'IF I HAVE NOT SEEN A CAMEL FLYING IN THE AIR', OR, 'IF I HAVE NOT SEEN A SERPENT LIKE THE BEAM OF THE OLIVE PRESS'; IF HE SAID TO WITNESSES, 'COME AND BEAR TESTIMONY FOR ME', [AND THEY REPLIED,] 'WE SWEAR THAT WE WILL NOT BEAR TESTIMONY FOR YOU'; IF HE SWORE TO ANNUL A PRECEPT, [AS E.G.,] NOT TO MAKE A SUKKAH, OR,
נשבע על דבר שאי אפשר לו אם לא ראיתי גמל שפורח באויר ואם לא ראיתי נחש כקורת בית הבד
NOT TO TAKE A LULAB, OR, NOT TO PUT ON TEFILLIN: THESE ARE VAIN OATHS, FOR WHICH ONE IS LIABLE, FOR WILFUL TRANSGRESSION, STRIPES, AND FOR UNWITTING TRANSGRESSION ONE IS EXEMPT. [IF A MAN SAID:] I SWEAR I SHALL EAT THIS LOAF; I SWEAR I SHALL NOT EAT IT,' THE FIRST IS AN OATH OF UTTERANCE, AND THE SECOND IS A VAIN OATH. IF HE ATE IT, HE TRANSGRESSED THE VAIN OATH; IF HE DID NOT EAT IT, HE TRANSGRESSED THE OATH OF UTTERANCE. <br>
אמר לעדים בואו והעידוני שבועה שלא נעידך נשבע לבטל את המצוה שלא לעשות סוכה ושלא ליטול לולב ושלא להניח תפילין זו היא שבועת שוא שחייבין על זדונה מכות ועל שגגתה פטור
GEMARA. Ulla said: Provided that it was already known to three men. IF HE SWORE CONCERNING A THING WHICH IS IMPOSSIBLE, [AS E.G., ] 'IF I HAVE NOT SEEN A CAMEL FLYING IN THE AIR.' T swear that I have seen,' he does not say! What [then] is meant by, 'If I have not seen ? Abaye said: Learn, I SWEAR I have seen.' Raba said: [The Mishnah means:] he said, '[I swear that] all the fruits of the world shall be prohibited to me, if I have not seen a camel flying in the air.' Said Rabina to R. Ashi: Perhaps this man saw a large bird, and gave it the name of camel, and when he swore, he swore according to his own mind; and if you say, we go according to his mouth, and we do not go according to his mind, [that cannot be,] for it has been taught: When they adjure him, they say to him, 'Know that we do not adjure you according to your own mind, but according to the mind of the Omnipresent and the mind of the Beth din.' What is the reason? Is it not because we say, perhaps he gave him counters, and called them zuzim, in which case when he swears, he swears according to his own mind? - No! There [the reason is] because of the cane of Raba. <br>
שבועה שאוכל ככר זו שבועה שלא אוכלנה הראשונה שבועת ביטוי והשניה שבועת שוא
Come and hear! And so we find that when Moses adjured the Israelites, he said to them: Know that I do not adjure you according to your own minds, but according to the mind of the Omnipresent and according to my mind. Now, why [should he say this]? Let him say to them: Fulfil what God has decreed. Is it not then because they might bring to their minds an idol? - No! But because an idol is also called god, for it is written: gods of silver, or gods of gold, [ye shall not make unto you]. - Well, let him say to them: Fulfil the Torah. - [That might have implied] one Torah. Let him [then] say: Fulfil the two Toroth. - [That might have implied] the Torah of sin offering and the Torah of trespass offering. [Let him say:] Fulfil the whole Torah. - [That might have implied merely the avoidance of] idolatry, for it has been said: Important is idolatry in that he who denies it is as if he accepts the whole Torah. Well, let him say to them: Fulfil the precept. - [That would have implied] one precept. [Let him say:] Fulfil the precepts. - [That might have implied merely] two. [Let him say: Fulfil] all the precepts. - [That might have implied] the precept of zizith, for a Master said: The precept of zizith is equal to all the precepts together. Then, let him say to them: Fulfil the six hundred and thirteen precepts. - But, even according to your reasoning, let him say. 'According to my mind;' why is it necessary to add, 'according to the mind of the Omnipresent'? <br>