- "הרי על כבכור"
The Gemara on the bottom of Daf 12b brought a Baraisa which taught: If one says: “הרי עלי כבכור” – “This meat is like a bechor towards me,” Rebbe Yaakov forbids the meat to the vower, but Rebbe Yehudah permits it. After rejecting the suggestion that this machlokes related to Rami bar Chama’s question regarding one who says that an item should be like the meat of a shelamim after the zerikah of the blood, the Gemara here clarifies the basis of the dispute. What is Rebbe Yehudah’s reason for permitting the item that was linked with the bechor? The passuk states: “כי ידור” – If a man vows a neder, עד שידור בדבר הנדור– the repetitive phrase implies that a neder through association does not work unless one associates it with something vowed, לאפוקי בכור דדבר האסור הוא - to exclude a bechor, which is something that is inherently prohibited. The Ran explains that since a bechor is automatically sanctified as an offering from birth, it is considered a דבר האסור – an inherently prohibited object. Rebbe Yaakov, who forbids the article, disagrees, as the passuk states: לה'" לרבות דבר האסור” – ”to Hashem,” which includes an association with something prohibited, referring to a bechor. The Gemara brings a Baraisa that explains that we learn from the passuk, “"הזכר תקדיש – the male shall you consecrate, שמצוה להקדישו - that it is a mitzvah to consecrate the bechor verbally. Rebbe Yehudah responds that the bechor would be sanctified even if no such declaration was made, and it is therefore not considered a דבר הנדור.
- "קונם פי מדבר עמך"
The Mishnah on 13b states: If one says: קונם פי מדבר עמך – “Konam, my mouth which speaks to you,” ידי עושה עמך – “my hand which works with you,” or רגלי מהלכת עמך – “my foot which walks with you,” the neder is valid and his friend is forbidden to benefit from these activities. The Gemara wonders how such a neder can be effective, since we learned that one area in which שבועות are more stringent than נדרים is שהשבועות חלות על דבר שיש בו ממש ושאין בו ממש מה שאין כן בנדרים - that oaths are effective both on that which is tangible and that which is intangible, as opposed to nedarim. The Ran explains that a shevuah takes effect on the גברא – the person, and a person has substance. which is not the case with nedarim, which take effect on items, but not activities. How, then, can one prohibit speech, etc. with a neder? The Gemara answers that the Mishnah is speaking of one who saidיאסר פי לדיבורי - “Let my mouth be forbidden for my speaking with you,” ידי למעשיהם – “my hands should be forbidden for their working with you,” or רגלי להילוכן – “my feet should be forbidden for their walking with you”. He thus has declared a neder on tangible items, which is effective.
- כבשר חזיר וכו'
The first Mishnah in the second Perek begins: ואלו מותרין - these are the vows that are permitted, i.e., ineffective. Among this list is one who says כבשר חזיר - your food should be like pork to me, כעבודת כוכבים- or like an idol, and several other examples. These illustrate the concept, mentioned briefly earlier, that one who makes a neder of התפסה - linking, in which he declares an item to be like a forbidden one, it must be done with a דבר הנדור - a vowed item, i.e., one which became prohibited through vowing, and not a דבר האסור - an item inherently forbidden . Pork, idols, and the examples which follow in the Mishnah, are all forbidden inherently, without a person’s declaration. The Gemara on 14a will provide the source for this rule.
