We all know that by Matan Torah took place the gerut of the Bnei Yisrael, the conversion of the Bnei Yisrael. And as the Gemara says in כריתות דף ט' עמוד א' that our forefathers who stood by הר סיני, לא נכנסו לברית אלא במילה וטבילה והרצאת דם, that they entered the brit with Hashem, which means that they were מגייר themselves through milah and through tevilah, milah which is circumcision, tevilah which is immersion they went to the mikveh, והרצאת דם which means they brought a korban. And the Gemara brings ראיות: milah, because the pasuk says כי מולים היו כל העם היוצאים ממצרים, that all the people who went out of Mitzrayim all were circumcised. Where do we see that they brought a korban at that time? Because the pasuk says in משפטים קפיטל כ\"ד פסוק ה', וישלח את נערי בני ישראל, he sent the נערי בני ישראל and they brought a korban. טבילה מנלן? Where do we see that the Yidden had to go tevilah? דכתיב, because the pasuk says in the same פרשה, משפטים קפיטל כ\"ד פסוק ח', ויקח משה את הדם, משה took the blood, ויזרק על העם, and he sprinkled on the people, ואין הזאה בלא טבילה. There is no such thing as sprinkling without first being טובל, first immersing in the mikveh. So from there we know that the Yidden immersed themselves in the mikveh. So the Yidden at that time had to go through the same these three things. From here we learn now that anybody who wants to enter Klal Yisrael, any goy who wants to be מגייר, has to go through the same three things: he has to go through milah and tevilah in the mikveh, and he has to bring a korban at the time of the Beit HaMikdash. If there is no Beit HaMikdash and you don't need the korban, and when Mashiach will come, then he'll bring the korban. Now, concerning the pesukim that we mentioned before, that the Gemara says that it says וישלח את נערי בני ישראל, and then it says that he sprinkled the blood, this was said, as I mentioned before, in the end of Parshas Mishpatim. But when was this done? So there's a machloket of Tannaim in the Mekhilta when this parshah was done. According to one Tanna in the Mekhilta, it was done on ה' b'Sivan, on the fifth day of Sivan. That's when Moshe Rabbeinu built a mizbeach, and he was makriv the korbanot, and he sprinkled the blood on the Yidden. And that's how the Gemara learns in Masechet Shabbat דף פ\"ח עמוד א', and Rashi in Chumash learns that way, too. But in the Mekhilta it says that רבי יוסי ברבי יהודה אומר, רבי יוסי ברבי יהודה says, בו ביום נעשו כל המעשים, on that on that day all this was done, which means on the day of מתן תורה. Now, the Ramban in Parshas Mishpatim, he brings the opinion of Rabbi Yosi bar Rabbi Yehudah, and he learns that this means on the day after מתן תורה. בו ביום means the day after מתן תורה. But in Midrash Lekach Tov it says clearly that the opinion that holds that all this was done בו ביום, it means that day, the morning of מתן תורה, before the עשרת הדברות. And the simple lashon of what Rabbi Yosi bar Rabbi Yehudah says, בו ביום נעשו, is also mashma that it means on that day, which is that famous day, the day of מתן תורה. So according to this that we're saying, that according to Rabbi Yosi bar Rabbi Yehudah, all this was done on the day of Matan Torah, likorah, we need an explanation, because that day we know was Shabbos, as the Gemara says in Maseches Shabbos דף פ\"ו עמוד ב', that דכולי עלמא בשבת ניתנה תורה לישראל. Everyone agrees that the Torah was given on Shabbos, whether it's according to the Rabbanan who hold it was the sixth day of Sivan or according to Rabbi Yosi who holds it was the seventh day of Sivan. But everyone holds that the day of Matan Torah was Shabbos.

Now, there is a halachah, a clear halachah that the Rambam paskens in Hilchos Issurei Biah, and it says in Shulchan Aruch Yoreh Deah סימן רס\"ח סעיף ד', that you are not allowed to be tovel a ger on Shabbos. So how were the Yidden on that day allowed to tovel themselves and become gerim? They were already מצווה על שבת, they were already commanded to keep Shabbos, because they were commanded to keep Shabbos in Marah, as the Gemara says in Shabbos דף פ\"ז עמוד ב', and it says that way in Yerushalmi Maseches ביצה פרק ב' הלכה א', or at least was given in Alush, as an opinion in Yerushalmi Beitzah, there as we mentioned, or as the opinion in Seder Olam פרק ה'. But whatever it is, whether it was given in Marah or in Alush, but it was definitely given before Matan Torah. So likorah, how were the Yidden allowed to tovel themselves on Shabbos, on the day of Matan Torah, and through that they were megayer themselves, when you are not allowed to tovel a ger on Shabbos to be megayer himself? Now, there is a possibility to say that Rabbi Yosi barbi Yehudah holds that the Torah was not given on Shabbos, because in the Mekhilta, in a different place, in on the פסוק in בשלח ט\"ז:א', it says that the sixth day of Sivan came out on Friday. So the Torah was given on a Friday. And that's how it also says in Pirkei DeRabbi Eliezer in the beginning of פרק מ\"ו, that it wasn't on Shabbos, which is not like it says clearly in our Gemara. that everyone holds was given on Shabbos. But in the Mekhilta there is an opinion that it was not given on Shabbos. So maybe Rabbi Yosi barbi Yehudah holds like that opinion. But we can't say that, because in Midrash Lekach Tov that we mentioned before, it says clearly: שבת קיבלו עשרת הדיברות, that on Shabbos they received עשרת הדיברות. And he continues that on that day they tovel'd themselves, and they had the sprinkling of the blood, and all these things it says were done bo bayom on that day of Matan Torah which was Shabbos. So we see clearly that it was on a Shabbos. So we're back to the question: How were they allowed to tovel the Yidden on Shabbos when you're not allowed to tovel a ger on Shabbos?

Now l'choirah you could answer this din that you're not allowed to tovel a ger on Shabbos is only a שבות דרבנן, it's from the דינים דרבנן, because there are two reasons given why you're not allowed to tovel a ger on Shabbos. In the Gemara in יבמות דף מ״ו עמוד ב׳ it says the reason is because תיקוני גברא בשבת לא מתקנינן. You're not allowed to fix a person on Shabbos, it's like fixing a kli. The Rambam says that the reason is that since טבילת גר, when a גר טובל's, does he need a beis din, that's why you can't be tovel on a Shabbos, because you are not allowed to have a din, a judgment on Shabbos, and since you need a beis din, it's like a judgment. Now according to both of these reasons, whether the reason is because you are מתקן גברא, you are fixing the person so to speak, or whether it is because you need a beis din, it's definitely only miderabbanan. So lichorah if it's only miderabbanan, that at that time it wasn't forbidden yet, and that's why they were allowed to do it. But it's still a dochak, because it's hard to say that the Bnei Yisrael entered the bris, which means they became an am of Hashem, and that was done through something that eventually later on became assur, even though at that time it wasn't assur. But the fact that later on it became assur, to say that the entering the bris, the beginning of the whole thing of Matan Torah started with something which will eventually become assur. And even though it's only איסור דרבנן, but we know what the Chazal say in יומא דף כ״ח עמוד ב׳ that קיים אברהם אבינו כל התורה כולה, that Avraham Avinu did the whole Torah, even עירוב תבשילין, which is only a דין דרבנן. And Rashi in Chumash in פרשת תולדות, קפיטל כ״ו פסוק ה׳ says that Avraham was even careful with a שבות לשבת, even a שבות which is an איסור דרבנן. So they knew about the איסורים דרבנן, and obviously many people were careful about the איסורים דרבנן. So how does it make sense to say that the Yidden entered the bris with Hashem and became an עם קדוש, and they went through their geirus in a way which was an איסור דרבנן, even if it wasn't forbidden at that moment? Now the truth is the question is even stronger: According to some meforshim, like the Ketonet Pasim and the Nimukei Yosef in Yevamot says, that according to the opinion of the Terumat HaDeshen that milah is assur on Shabbos because of the melachah of תיקון כלי, of מכה בפטיש, and you're not allowed to finish off a kli, and that's why you're not allowed to do milah on Shabbos, so the Ketonet Pasim says that according to this opinion, if a גר טובל's on Shabbos, it's an איסור דאורייתא. So according to him, the question is even stronger: How were they able to become gerim at that time when they just started the inyan of being an am of Hashem, it should be done through something which is an איסור דאורייתא?

Now the answer to this is, let's first understand, in order to become a ger, and the same thing at that time when the Yidden, the whole Klal Yisrael was megayer themselves, we mentioned before it had to be done through three things: milah, and tevillah, and הרצאת דם, which means circumcision, going to the mikveh, and bringing a korban. But lichorah there is another thing which is not mentioned there at all which is very important, and that is קבלת מצות, that the ger has to accept upon himself to keep all the mitzvot. And the Yidden that time also had to accept upon themselves keeping all the mitzvot, and they said נעשה ונשמע לכאורה. So why isn't that mentioned? And the answer is very simple: קבלת מצות, to receive the mitzvot, is not a condition of how to become a ger. That is the gerut itself! That is what conversion is. Conversion means when a goy wants to become a Yid. What does it mean to become a Yid? He wants to accept upon himself Torah u'mitzvot. So there are conditions and things he has to do in order to be accepted, and that is he has to have milah and tevillah and bring a korban. But the קבלת מצות, if that's missing, it's not a pshat you're missing one of the conditions of how to become a Yid. You're missing the whole geirut, because the whole geirut is that. And the same thing with the Bnei Yisrael then. So now that we say that קבלת מצות is the whole ענין of geirut, we will understand why at that time the Bnei Yisrael were allowed to go through the process of geirut on Shabbos, and they were allowed to טובל themselves on Shabbos according to Rabbi Yosi bar Rabbi Yehudah, and become geirim at that time. Because, as we'll see in a moment, what happened at that time when the Yidden accepted the mitzvot, when they went to the mikveh at that time before the עשרת הדיברות were said to them, is not the real thing of them becoming geirim at that time. Nowadays, when a person becomes a ger, and he accepts the mitzvot at the time when he טובל's himself, then that that is the real קבלת המצוות, and that's when he becomes a ger. And that's why that is not allowed to be done on Shabbos, because whether it is because you need a beit din for that, or whether it is because this is תיקון גברא or תיקון כלי, it's finishing off the person, that's why it's forbidden. But it's all because at the time when he טובל's himself and he accepts the mitzvot at that time, that's the moment he becomes a ger. But by the time of Matan Torah, as we will see in a moment, when the Yidden went through the טבילה and the Yidden accepted to do the mitzvot, this did not make them become a ger yet. They were not geirim. They were not geirim till afterwards when השם actually said to them the עשרת הדברות. And therefore, this was not their תיקון גברא. When they went to the mikveh, this did not finish off their geirut. And this did not really need a beit din because this was not the gerut itself. This was the preparation to the gerut, but the real גרות took place at the moment when Hashem said, \"אנכי השם אלקיך.\" The explanation to this is because we know when Hashem said, \"אנכי השם אלקיך,\" to the Bnei Yisrael by עשרת הדברות, at that moment there was such a revelation of Godliness that never before was there. There was something that took place at that moment that was never there before. As it says in the Midrash, the famous, in Tanchuma Vaera ט\"ו and Shemot Rabbah פרשה י\"ב, ג', that when Hashem created the world, גזר ואמר, He made a gezerah and He said, \"השמים שמים להשם והארץ נתן לבני אדם.\" The שמים is to Hashem, and the ארץ is to the בני אדם. כשביקש ליתן את התורה, when He wanted to give the תורה, ביטל את הגזירה הראשונה, השם nullified the first גזירה, ואמר, and He said, \"התחתונים יעלו לעליונים, והעליונים ירדו לתחתונים.\" The ones from below will go up to the ones above, the ones from above will come down below. \"ואני המתחיל,\" Hashem said, \"I will be the first.\" שנאמר, \"וירד השם על הר סיני,\" Hashem came down to Har Sinai. So from this Midrash, we understand that even though we find the hitgalut of Hashem, the revelation of Hashem, to tzaddikim and to neviim before Matan Torah, but still, being it before Matan Torah, there was a gezerah, as the Midrash calls it, the גזירה ראשונה, that there should be a separation between elyonim and tachtonim, between the higher and the lower, between the Godliness and the physical world. So whatever was there before, all the revelations that were before, we can't consider it that the Shechinah, the elyonim, actually came down lematah. In truth, they never it never came down lematah. And as it says in many places that before Matan Torah, there was no שלמות, no complete התגלות of Hashem, revelation of Hashem. By Matan Torah, that's when there was this התגלות of \"אנכי השם אלקיך.\" Hashem said, \"I am God your God.\" That's when the גזירה was batel, and that's when this revelation, the true revelation of Hashem, came into this world. So from that we understand that even concerning Moshe Rabbeinu himself, we know that Hashem revealed Himself to Moshe Rabbeinu by the סנה, by the burning bush and other places, still, this was not at all in the same category as the התגלות of Hashem, the revelation of Hashem, that took place at the time when Hashem came down to Har Sinai and said the עשרת הדברות. And therefore, all the mitzvot that were given by Hashem before, which came obviously through the התגלות, the revelation of Hashem, nevertheless, when Matan Torah came, we say, \"ניתנה תורה ונתחדשה הלכה.\" The Torah was given, and there's a new halachah. All the old halachot were batel. As the Rambam says in Pirush HaMishnayot, in the end of the seventh perek of Chullin, he says that שכל מה שאנו מחזיקים or עושים היום, whatever we're doing today or not doing, \"אין אנו עושים אלא במצות הקדוש ברוך הוא על ידי משה רבינו עליו השלום מסיני.\" We're only doing it because Hashem said it to Moshe Rabbeinu in Sinai, and not because Hashem said it to any נביאים שלפניו, of any other נביאים. And even not because Hashem said it to Moshe Rabbeinu before Matan Torah. And therefore we can understand that when the Yidden accepted upon themselves נעשה ונשמע before Matan Torah, which was the קבלת המצוות that they did, this was not the קבלת המצוות, this was not the acceptance of the mitzvot, of the mitzvot the way they really were. Because at that time, before Hashem said, \"אנכי השם אלקיך,\" the way the mitzvot were, were in a complete different level than the way the mitzvot are after Hashem said, \"אנכי השם אלקיך,\" and the mitzvot that were given from that moment and on. So this would be similar to the din that you have to notify a ger all the קלות וחמורות, all the easy mitzvot, the strict mitzvot, etc., etc. And the din is that if you did not notify the ger the strict mitzvot or the onshim, the punishment of the mitzvot, then the gerut is not a gerut. And the simple reason is why? Because maybe he'll be able to say later, \"Had I known the strictness of the mitzvot, I wouldn't accept it.\" But whatever the point is, in any event, it means that when he accepts upon himself the mitzvot, it has to be a complete kabbalah of the mitzvot the way they are. So therefore he has to know all aspects of the mitzvot. The Bnei Yisrael, when they accepted upon themselves the mitzvot before the עשרת הדברות were said to them, and when they went to the mikveh, Based on their kabbalah, it was not really an acceptance of the mitzvot the way the mitzvot will be later, because at that time, the way the mitzvot were later did not exist yet. Because at that time, all the mitzvot were, were only according to the level of התגלות השם, the revelation of Hashem, the way it was before Matan Torah. But the mitzvot that have this התגלות of Hashem the way it's after Matan Torah didn't exist yet, and since it didn't exist, we can't say that they accepted it. So when did that come? It only came after Hashem came down to Har Sinai and said to them אנכי ה' אלקיך and the rest of the עשרת הדברות, at that moment, there was this התגלות השם. So when did really the geirut take place? When was the end of the geirut, the completion of the geirut? At the time when Hashem came down to הר סיני. So then the acceptance that they did before, then because now they already knew this new התגלות of Hashem, the new revelation of Hashem, and they understood the level of the mitzvot the way they are now, and they still continued in their acceptance that they said before, now they became gerim. Because as we said before, kabbalat hamitzvot is not just an important matter, but this is the geirut itself. So therefore, it has to be proper. When was the real acceptance of the mitzvot? At the time when Hashem said אנכי ה' אלקיך. At that time, they didn't do anything, they just accepted it. The kashya we had in the beginning was that according to R'' Yosi, R'' Yehudah, how were they able to do something, go to the mikveh, which would end the geirut, make their geirut, that you're not allowed on Shabbos? But as we're saying now, when they went to the mikveh and they accepted it, the mitzvot at that time, this was not the end of the geirut at that time, because it couldn't have been. So therefore, that was allowed to be done, and all the issurim on Shabbos don't apply, because it only applies in the case where they're going to the mikveh is the גמר הגירות, is the completion of the geirut. And when did the completion of their geirut take place? When Hashem said to them אנכי ה' אלקיך, and this great new type of revelation of Hashem came down to this world.