Shevuot 51
ר' ישמעאל אומר אינו חייב אלא על העתיד לבא: ת"ר (ויקרא ה, ד) להרע או להיטיב אין לי אלא דברים שיש בהן הרעה והטבה שאין בהן הרעה והטבה מנין תלמוד לומר (ויקרא ה, ד) או נפש כי תשבע לבטא בשפתים
R. ISHMAEL SAYS, HE IS LIABLE ONLY FOR [AN OATH IN] THE FUTURE. Our Rabbis taught: To do evil, or to do good. [From this] we know only such cases where doing evil and doing good are applicable; but how do we know such cases where doing evil and doing good are not applicable? Because it is said, Or if anyone swear clearly with his lips. [From this] we know only [oaths in] the future; how do we know [oaths in] the past? Because it is said: Whatsoever it be that a man shall utter clearly, with an oath. This is the opinion of R. Akiba. R. Ishmael says: To do evil, or to do good implies the future. R. Akiba said to him: If so, we know only such cases where doing evil and doing good are applicable; how do we know such cases where doing evil and doing good are not applicable? He replied to him: From the amplification of the verse. Whereupon he said to him: If the verse amplified for that, it amplified for this also. Well did R. Akiba reply to R. Ishmael! - R. Johanan said: R. Ishmael who ministered to R. Nehunia b. Hakanah, who expounded the whole Torah on the principle of generalisation and specification, also expounded it on the principle of generalisation and specification; R. Akiba who ministered to Nahum of Gamzu, who expounded the whole Torah on the principle of amplification and limitation, also expounded it on the principle of amplification and limitation.
אמר לו רבי עקיבא אם כן אין לי אלא דברים שיש בהן הטבה והרעה דברים שאין בהן הרעה והטבה מנין אמר לו מרבוי הכתוב אמר לו אם ריבה הכתוב לכך ריבה הכתוב לכך
taught: Or if any one swear [clearly with his lips - this amplifies; to do evil, or to do good - this limits; whatsoever it be that a man shall utter clearly [with an oath] - this again amplifies: because it amplifies, limits, and amplifies, it includes all; what does it include? It includes all things. What does it exclude? It excludes a precept. And R. Ishmael expounds it on the principle of generalisation and specification: or if any one swear clearly with his lips - this generalises; to do evil or to do good this specifies; whatsoever it be that a man shall utter clearly [with an oath] - this again generalises: because it generalises, specifies, and generalises, you may include in the generalisation only [those oaths which are] similar to the specification: just as the specification is clearly in the future, so all [oaths] in the future [may be included]; the generalisation helping to include even cases where doing evil and doing good are not applicable [as long as they are oaths] in the future; and the specification helping to exclude even cases where doing evil and doing good are applicable [if they are oaths] in the past. Let me reverse it! - R. Isaac said: [We include only oaths] similar to [the oath] to do evil, or to do good, where the prohibition is on account of he shall not break his word, but exclude this [oath] where the prohibition is not on account of he shall not break his word, but on account of ye shall not lie. R. Isaac b. Abin said: Scripture says, Or if any one swear clearly with his lips: the oath must precede the utterance, and not the utterance precede the oath; this excludes 'I ate', or, 'I did not eat,' where the action precedes the oath.
שפיר קא"ל רבי עקיבא לר' ישמעאל
Our Rabbis taught: [Whatsoever it be that] a man [shall utter clearly] with an oath - this excludes [a false oath by] accident; and it be hid - this excludes wilful [transgression of oath]; from him - [this implies that] the oath was hidden from him. I might think that [even] if the thing be hidden from him [he should be liable], therefore it is said: . . . with an oath, and it be hid ... for the unawareness of the oath he is liable, and he is not liable for the unawareness of the thing. The Master said: '.. . a man . . . with an oath - this excludes [a false oath by] accident'. How is this? As the case of R. Kahana and R. Assi: when they rose from [the lecture of] Rab, one said, 'I swear that thus said Rab,' and the other said, 'I swear that thus said Rab.' When they came [again] before Rab, he would agree with one of them; then the other would say to him, 'Did I, then, swear falsely?' He would reply to him, 'Your heart deceived you.' <br>
א"ר יוחנן ר' ישמעאל ששימש את רבי נחוניא בן הקנה שהיה דורש את כל התורה כולה בכלל ופרט איהו נמי דורש בכלל ופרט רבי עקיבא ששימש את נחום איש גם זו שהיה דורש את כל התורה כולה בריבה ומיעט איהו נמי דורש ריבה ומיעט
'And it be hid from him - [this implies that] the oath was hidden from him. I might think that [even] if the thing be hidden from him [he should be liable], therefore it is said: . . . with an oath, and it be hid ... for the unawareness of the oath he is liable, and he is not liable for the unawareness of the thing.' They laughed at this in the West. Granted, [unawareness of] oath is possible without [unawareness of] thing; for example, if he said, I SWEAR I shall not eat wheat bread,' and he thought he had said, T shall eat,' his oath he forgot, and the thing he remembered. But [unawareness of] thing without [unawareness of] oath - how is that possible? If for example, he said, I SWEAR I shall not eat wheat bread,' and he thought he had said 'barley [bread],' his oath he remembered, and the thing he forgot. - Since he forgot the thing, it is [automatically] unawareness of oath! - Well then, said R. Eleazar, this and that are one. <br>
מאי ר' עקיבא דדריש ריבויי ומיעוטי דתניא או נפש כי תשבע ריבה להרע או להיטיב מיעט לכל אשר יבטא האדם חזר וריבה ריבה ומיעט וריבה ריבה הכל
R. Joseph demurred: This means that [unawareness of] thing without [unawareness of] oath is by no means possible? But surely it is possible; for example, if he said, I SWEAR I shall not eat wheat bread,' and he stretched out his hand to the basket to take barley bread, but wheat [bread] came to his hand, and he, thinking it was barley [bread], ate it: now, his oath he remembered, but it was the thing that he did not know! - Abaye said to him: But do you not make him liable for an offering for that which he holds in his hand? It is, therefore, unawareness of oath. Another version: Abaye said to R. Joseph: In any case, he should bring an offering for this bread, for it is unawareness of oath. And R. Joseph? - He may reply to you: Since, if he had known that this was wheat, he would have refrained from [eating] it, it is unawareness of thing.
ור' ישמעאל דריש כלל ופרט או נפש כי תשבע לבטא בשפתים כלל להרע או להיטיב פרט לכל אשר יבטא האדם חזר וכלל כלל ופרט וכלל אי אתה דן אלא כעין הפרט מה הפרט מפורש להבא אף כל להבא
thing, he should be exempt! - R. Ashi said: We observe, if because of the oath he refrains, it is [a case of] unawareness of oath, and he is liable; and if because of the thing he refrains, it is [a case of] unawareness of thing, and he is exempt. Said Rabina to R. Ashi: Does he then refrain because of the oath unless it be also because of the thing, and does he refrain because of the thing unless it be also because of the oath? There is really no difference. <br>