Because up until this point we have the words of the Omnipresent. Rashi is answering the question: It is obvious that he said [over] all that Hashem had commanded him! Furthermore, in the entire Torah it mentions the command alone, so why here does it mention the command and also Moshe’s words to Yisroel? He answers that “because…”

By teaching them first. Rashi is answering the question: Why is it written, “To the tribal leaders”? One cannot say this passage was only said to the tribal leaders, and not to all of Israel. For here it states, “This is the word” in order to learn a gezeirah shavah [scriptural comparison] as Rashi explains shortly, to teach that this passage was said to all of Israel. If so, why is it written, “To the tribal leaders”? Rashi answers that it is to “bestow honor…” Accordingly the meaning of “To the tribal leaders of Bnei Yisroel” is “[To the tribal leaders] and to Bnei Yisroel.” Re’m. We cannot say that perhaps the verse means “To the tribal leaders of Bnei Yisroel” because if so, why would it have been necessary to write “of Bnei Yisroel” given that it would have been sufficient to just say “To the tribal leaders, saying…” Rather, one must say that it was informing us of the order of teaching, as Re’m explained and as Rashi will explain shortly. Alternatively, Rashi is answering another question: Why did the verse write ראשי המטות לבני ישראל [lit. "to the tribal leaders, to Bnei Yisroel"] when it should have said אל ראשי מטות בני ישראל ["to the tribal leaders of Bnei Yisroel"]? Rather, since the verse was written in this way one must say that “tribal leaders” is considered a construct, meaning that the word “tribal” is a construct with the word “leaders.” Consequently the word “Yisroel” is distinct, not a construct with the word “tribal,” rather it is an independent word. Thus one is obliged to explain as follows: Initially Moshe said this to the tribal leaders and afterwards to Bnei Yisroel, and it is as if it had written “and to Bnei Yisroel.” This was the honor bestowed upon them, that he taught them first and afterwards the Bnei Yisroel. Accordingly it is also understandable why the Torah did not write, “Hashem spoke to Moshe saying: Speak to Bnei Yisroel: If a man makes [a vow]…” Rather the verse must be coming to inform us of the order of teaching, writing “Moshe spoke” as if to say, “This was [the order] of Moshe’s speech to Yisroel.” This is the essence of Rashi’s explanation according to Toras Kohanim, however in Gemara Nedarim (78a) it is expounded differently.

Why, then, did he see fit to say this here? Meaning that because throughout the entire Torah honor had been bestowed upon the leaders, as it is written, “They returned to him, Aharon [and all the leaders…].” Why was this taught again here?

Vows may be annulled by a single expert. When the Sage comes to permit a vow, he removes it retroactively as if there had never been a vow. With this sanction, the vow is annulled as if there had never been one; therefore Rashi uses the term הפרה ["annulment"].

By three laymen. [Rashi says this] because “Tribal leaders” implies that there was one leader who could annul the vow, namely the one expert. You might ask: Surely it is written “leaders” in the plural form? The answer is that it speaks of leaders in general, referring to all the tribal leaders. Now, since one expert was required, then three laymen would be needed. [We derive the number as follows:] It is logical that we would need more laymen than experts. However, it is not possible [that we require only] two, given that a court can never be evenly balanced. Thus, we add an additional one, totaling three. We need not ask that perhaps more than three, because if so there would be no end to the matter.

Only to the leaders. And accordingly, לבני ישראל ["of Bnei Yisroel"] would mean for Bnei Yisroel, meaning that he taught the leaders so that they would teach Yisroel, but Moshe did not teach everyone for that would not be necessary here. [One might have thought so] since the annulment of vows requires people appointed over Yisroel, in order to instruct them as to which vows one is unable to annul and which one is able to annul. Therefore, here it would have been sufficient to have the leaders instruct them. Thus, Rashi answers that “here it says…”

Moshe prophesied… You might ask: “This is the word” was necessary for the gezeirah shavah [scriptural comparison] above, as Rashi explained. The answer is that here one cannot question the gezeirah shavah, therefore it does not need to be superfluous [and one can also expound the simple meaning].

With the phrase “this is the word.” This is an additional distinction, for “This is the word” implies that it is the word itself, which was clearly heard from Hashem in what is termed a “clear vision.” This was not so for the other prophets, as Hashem spoke to them only in riddles or through dreams, termed as “unclear visions.” But to Moshe He spoke “the word” itself, so that he could tell it to Bnei Yisroel. Likewise, it states (Bamidbar 12:8), “Mouth to mouth I speak to him, in vision and not in riddles.” [One might ask what was meant] when Moshe prophesied with the words “So says Hashem” as it is written in Parshas Va’eira (Shemos 8:26) and in Parshas Bo (Shemos 10:3). The answer is that before he stood on Mount Sinai he would prophesize with “So [says Hashem]” however after the Torah was given he prophesied with “This is the word [of Hashem],” once his face began to emit beams of light.

Another interpretation: “This is the word” is exclusionary. According to the first explanation, there is the difficulty of why it did not say this for all of the mitzvos. Therefore Rashi explains that “this is the word…” However, one cannot say that it was only said for this [second] reason, for if so why did the Torah say, “The word that Hashem commanded…”? It should have said explicitly what is excluded. Therefore, the first reason is also necessary.

The Sage with the term “release” and the husband with the term “nullification.” The Sage only releases [the vow] when there is regret, therefore the term “release” is suitable. However the husband nullifies without regret and without providing any reason, thus the term “nullification” is appropriate.

Following the Scriptural language here. For it is written (v. 3) “If a man makes a vow…to initiate a prohibition himself, he may not profane his word” which implies that he may not profane his word, however another [i.e., Sage] may "profane" it for him. Furthermore, it is written לאסור איסר ["to initiate a prohibition"] which implies that he prohibited a certain article upon himself and another person can come and release him from the prohibition. It is regarding “prohibition” the term “release” is appropriate, for איסור ["prohibition"] has the connotation of a knot, making the term מתיר [lit. "untying, releasing"] appropriate — just as one unties a knot. Hear from this that the term התרה ["release"] refers to the Sage.

A konam that I will not eat. Meaning that he says, “Let this article be like a konam to me, that I will not eat…” Though [a statement] prohibiting one from eating is applicable to a שבועה ["oath"] rather than a נדר ["vow"], as Ramban asks, this has already been answered by Re’m. See there.

Like לא יחלל. Thus, it is one of the doubled roots and had it not been a [a letter] ches, which does not take a dagesh [dot], it would have had a dagesh in order to complete the doubling. [Here the root is doubled, thus it should have been חלחל. However a dagesh in the ches would have substituted for the second letter ches]. [לא יחלל] means, “He should not belittle his words” as one belittles unsanctified property without concern of guarding it from impurity, as [one guards only] sanctified property from impurity.

Under her father’s jurisdiction. At the end of this passage it is written, “In her youth, while in her father’s house” (v. 17) which is apparently superfluous, given that here it is written, “In her father’s home while still in her youth.” Rather, it comes to teach you that all the profits of a youth belong to her father, and this is even if she is not in his house, since “In her father’s house” is not to be taken literally. Similarly, here, “In her father’s home” means under his jurisdiction and not literally in his house. Re’m.

But not a minor. Meaning that her vows are not definite vows, rather there are those whose vows must be examined, and there are those that are not vows at all, as explained.

I would not know what this הנאה means. You might ask: Surely without that verse Rashi would still know the meaning of הנאה, for afterwards he brings the verses למה תניאון ["why do you turn away"] and אל יניא ראשי ["not turn my head"]. [Re’m] brings many more difficulties. The answer is as follows: Initially Rashi explained “He restrained her from the vow” in accordance with his later explanation that “Its plain meaning is [to restrain…].” However, since it said, “If he restrained her” I might have said that he could annul the vow solely with words, by saying, “I do not wish this vow to stand.” Therefore Rashi explained that “In other words, he nullified it.” Meaning as the Sifri teaches, that he has to explicitly nullify the vow saying, “Let it be nullified for you.” But if he did not say so and merely restrained her, then it is not annulled. It is in relation to the Sifri that Rashi says, “I would not know what this הנאה means,” meaning that according to Sifri “If her father הנאה ["restrained"] her” is in the sense of nullification, and I would not know how הנאה implies nullification. However, since the Sifri explained that at the end of the passage it says regarding the husband, “But if on the day her husband hears about it, he restrains her and then annuls” (v. 9) we see that הנאה in the context of the husband is nullification. Thus it would be logical to say that הנאה here in the context of the father is also nullification. For if it merely meant restraint, the verses would be contradictory, for “Her father restrained her” would imply mere restraint while “restrain” in the context of the husband would imply nullification, that he said, “Let it be nullified for you,” because it is written, “If… he restrains her and nullifies.” Therefore, one must say that “nullify” is the explanation of “restrain” and we see that הנאה written in the context of the father is also nullification, only that [here] the Torah wrote הנאה in place of nullification. Nonetheless, its plain meaning is to restrain and turn aside as Rashi explains above, bringing proof from Scripture. Afterwards (s.v. ‘will forgive her’) Rashi raises a difficulty: Since “Her father restrained” implies actual nullification, why is it written, “Hashem will forgive her”? Why would she need forgiveness if she did not sin, given that her vow had been annulled? He answers that regarding the husband it also writes, “Hashem will forgive her” (v. 9) and, “To whom does Scripture refer? To a woman who made a [Nazirite] vow…” This is a woman who needs forgiveness, even though the vow was annulled. So too, regarding the father and daughter, it refers to a daughter who made a Nazirite vow where her father heard… She too needs forgiveness, since she was not aware that it was nullified, and transgressed her vow, as Rashi explains. He expands more upon this, see there. (Kitzur Mizrochi). Regarding Rashi’s comment about the youth, that if she took a Nazirite vow and he nullified it etc., Mahari raises the difficulty that there is no punishment in the heavenly court until the age of twenty. He answers that this could be where she vowed not to eat meat for twenty years, meaning her vow continued until after she had reached twenty, and became independent. If she then transgressed her vow, she would require atonement. He discusses this at length but finally he raises the difficulty with his answer that it is inconceivable that she would not hear or know about the nullification until the age of twenty. It appears to me that the matter is not dependent upon any punishment, for even an older woman would not be punished, given that her husband had annulled the vow. However, there would still be some blemish to her soul. Here too with the youth, since she knew to whom she made the vow [in the case where she was a minor], and all the more so if she was older than twelve where she would be liable to punishment in the earthly court, her soul would be somewhat blemished because her intention was to sin.

But perhaps to a “nesuah.” Meaning that although the plain understanding of הויה [lit. "being" having the connotation of marriage] refers to kiddushin [betrothal], nonetheless, we also find הויה referring to relations as in “his virgin [sister] who is close to him, who was not היתה ["married"] to a man” (Vayikra 21:3) where [היתה] refers to relations, meaning she was a nesuah. Thus, I would have said that הויה here also refers to relations and a she was a nesuah, such that both the father and the husband would annul her vow. However “when it says…”

So this must mean an “arusah.” For here it is written ואם היו תהיה לאיש ["if she is married to a man"] which is in the sense of הויה ["marriage"] and kiddushin.

That her father and husband annul her vow. Meaning that the Torah did not group them [the nesuah and arusah] together so that it could distinguish between them, teaching about an arusah that her father and husband annul her vow, which is not the case for a nesuah. Afterwards Rashi explains that one should not say that [between] her father and her husband one of them can annul it, for this is not so, because “if the father annulled…” as is explained in the continuation of the passage.

If one of them endorsed it. We have said that if one annulled and one was silent then it is not annulled. Even more so if one endorsed, the other would not be able to annul.

But her father did not hear them — they were neither annulled. Because if the father annulled [the vows], they would not have to be annulled any further.

Nor endorsed. Because if the father endorsed [the vows], the husband’s annulment would not help. [In the case of an arusah] if the father did not annul while the husband did, it would not help, as Rashi explained above that “[if the father] annulled but not [the husband]…” Consequently, even more so if the father endorsed the vows, they could not be annulled by the husband’s annulment.

Perhaps even if the father did not annul… (Nachalas Yaakov) There is no doubt that [the title of this comment, as it appeared in the text of the Sifsei Chachamim] is a copyist’s error, for that verse (v. 13) refers back to “If she took the vow in her husband’s home” (v. 11) and the case where she was married. However, the text of Re’m is correct, for [its heading] reads, “He then annuls her vow.”

All through her youth she is under her father’s jurisdiction. Rashi means to say that above when it is written (v. 7) ואם היו תהיה לאיש ["and if she is married to a man"], it should have written אם תהיה ["if she is married to a man"]. However, the [letter] vav links it to the previous subject where it is written (v. 6), “Her father restrained her…” [i.e. where the father annulled her vow]. Consequently, when we expound that "all the profits of a youth belong to her father" from the verse, “In her youth, while in her father’s home” (v. 17) this also implies that here she would require the annulment of her father. Thus, there is no difference between an arusah and an unmarried girl, for the [conjunctive letter] vav links it to the previous subject where she was also under the jurisdiction of the father, and would refer to an arusah who is under the jurisdiction of both [the husband and the father]. Re’m explains that if it had referred specifically to an unmarried girl, but that the jurisdiction of the father had been removed from an arusah, why is it necessary to say “In her youth, while in her father’s house” (v. 17) a second time? Surely it had already written “In her father’s home, in her youth” (v. 4). Both of these explanations are in the Gemara, as Re’m also mentions. Thus, the verse, “If she is married” refers to a woman who imposed a prohibition [on herself] in her father’s home during her youth, where her vow was still upon her since her father had not heard about it. Subsequently, if after she became betrothed her father heard about it, he would also be party to its nullification.

A widow after nisuin. The explanation is as follows: A widow is not under the jurisdiction of the father and a divorcee is not under the jurisdiction of the husband regarding the nullification [of vows]. You might ask: Why would one think that he could annul [the vow]? The answer is that once we find that the husband can annul a vow even if it was not made under his jurisdiction, such as where she made a vow in her father’s house, [one would have said] all the more so that he could annul [this vow] for her, since she made it under his jurisdiction. Therefore, Rashi explains that she is not under the jurisdiction of the husband.

Scripture refers to a nesuah. (Gur Aryeh) The reason why the Torah did not place “But if she took a vow in her husband’s home” before the verse, “The vow of a widow” (v. 10) which speaks about a case after marriage, is because the Torah was not being specific when it said, “Widow or a divorced woman.” For the same holds true for an adult who is unmarried, [since] the father does not have jurisdiction over her, her vow stands like that of a widow. Thus the verses are in order, for first it speaks of a youth who is under the jurisdiction of her father entirely, and afterwards, “And if she was married to a man” where she is under the jurisdiction of her father and her husband. Then [it refers to] a woman who is not under the jurisdiction of the father [i.e.] a widow or a divorced woman, with the same being true for an adult. Next, [it refers to] a nesuah who is entirely under the jurisdiction of her husband.

He may only annul vows which are self-denial. For example, that she may not taste anything [that I prepare] or that she may not drink any beverage.

So that you should not say [he may annul] for twenty-four hours. Rashi wishes to answer the question: Why is it necessary to write, “From one day to the next”? We cannot say it comes to teach that if he did not annul it on the day he heard, he can no longer annul it. For the Torah had already written (v. 8), “And her husband heard about them and remained silent on the day he heard, then [her vows] shall stand.” Rashi answers that if it had not written, “From one day to the next” one might have said that previously when it wrote, “On the day he heard” this was [measured] from "moment to moment," namely a twenty-four hour period.

Until nightfall. Meaning that if he heard during the day, even if it was close to sunset, once he remained silent until nightfall he can no longer annul.

Saying, “I approve.” Rashi wishes to answer the question: Why is it written, “If he annuls them after having heard them, he must bear her transgression” which implies that if he annuls them immediately after hearing, he will bear her transgression? But surely [in doing so] he has acted appropriately. We cannot explain that if he heard and endorsed, then later annulled on the same day, they would be annulled. For if so, why does the Torah say, “After having heard them” which implies that if he did not annul her vows immediately upon hearing them, he may not go back and annul them? Therefore, one must say that if he heard her vow and said, “I approve” that he can no longer annul it, even during the same day.