Concerning the fast day of עשרה בטבת, the Avudraham writes in Hilchos Taaniyos, and it's also brought down in the Beis Yosef Orach Chaim סימן תק\"נ, he says that אפילו היה חל בשבת, even if עשרה בטבת would have come out on שבת, לא היו יכולין לדחותו ליום אחר, we wouldn't be able to push it off for another day, מפני שנאמר, because the pasuk says בעצם היום הזה, concerning what happened on עשרה בטבת it says בעצם היום הזה. In בעצם, the middle, the essence of the day, that's when Nevuchadnetzar surrounded ירושלים, כמו ביום הכיפורים, just like by Yom Kippur it says בעצם היום הזה you have to fast, and therefore we fast even if Yom Kippur comes out on Shabbos, so he says that if עשרה בטבת would be able to come out on Shabbos, we would have to fast on עשרה בטבת. And even though בפועל עשרה בטבת now cannot come out on Shabbos ever, nevertheless he just wants to bring out the importance of עשרה בטבת, that the obligation of fasting on that day is so strong that if it would be able to come out on Shabbos, then we would have to fast on Shabbos also. And in truth, even though בפועל it cannot come out on Shabbos, so it seems like that what the Avudraham is saying is not נוגע להלכה at all, because it's just a theory, because בפועל עשרה בטבת could never come out on Shabbos, it is נוגע להלכה at the time when they were still מקדש על פי הראיה after the חורבן בית המקדש, because we know that even after the חורבן בית המקדש there was a time when they used to establish the calendar based on the witnesses that would come and testify that they saw the moon, and when they were מקדש על פי הראיה, it was possible that עשרה בטבת would come out on Shabbos. And since it was already after the חורבן בית המקדש, so they fasted on עשרה בטבת, so this din that the Avudraham says that עשרה בטבת comes out on Shabbos you have to fast was נוגע להלכה at that time, and it could still be נוגע להלכה according to those דעות that hold that there's a possibility of having a Sanhedrin even before Mashiach comes, as the שיטה of the Rambam in Peirush HaMishnayos in Yad Hachazakah as is explained in many sefarim. If we will have the Sanhedrin before Mashiach, and they will be מקדש על פי הראיה then, so it's possible that then Asarah b'Tevet will come out on Shabbos, we'll still have to fast, because this will be before Mashiach if it happens, so then this could be נוגע להלכה. Now in truth, this is only the שיטה of the Abudraham, but it seems from Rashi in Megillah דף ה עמוד א דיבור המתחיל אבל that Rashi doesn't hold of that, because when it says there that if a fast day comes out on Shabbos you postpone it, you push it off for Sunday, so Rashi says והוא הדין לי\"ז בתמוז ולעשרה בטבת, and the same din applies to Shivah Asar b'Tammuz and to Asarah b'Tevet. So it seems like Rashi learns that if Asarah b'Tevet would come out on Shabbos, we would have to push it off, not like the Abudraham. But the She'elot u-Teshuvot Mahadura Kama חלק ג סימן קע\"ט explains how Rashi does fit with the Abudraham. But on the other hand, in the Rambam it is משמע not like the Abudraham, because the Rambam in הלכות תעניות פרק ה הלכה ה, he writes that אחד מארבעה ימי הצומות, if one of these four fast days, which includes Asarah b'Tevet, would come out on Shabbos, you have to postpone it to Sunday. So we see there it seems that the Rambam holds that you would postpone it to Sunday, not like the Abudraham. But nevertheless, this is the שיטה of the Abudraham. The Beit Yosef writes on the אבודרהם ולא ידעתי מניין לו זה, I don't know where he takes this from, but in the Knesset HaGedolah, which is brought down in the Eliyah Rabbah there, it says that in Sefer Tikkun Yissachar they bring it in the name of the Teshuvos Hageonim. So it seems like there is a makor for what the Abudraham says in the Teshuvos Hageonim that Asarah B'Tevet, if it comes out on Shabbos, you still have to fast on Shabbos. And the truth is, even according to those that hold that if Asarah B'Tevet would come out on Shabbos we wouldn't have to fast on Shabbos, but nevertheless we see a chumra in Asarah B'Tevet לגבי all other fast days, because only Asarah B'Tevet is possible to fall out on Friday, and the din then is that you have to be משלים the ta'anit till צאת הכוכבים, that you're not allowed to eat till צאת הכוכבים, till the stars come out, and it becomes Shabbos. And this would be even if the person daven Maariv earlier. You're allowed to daven Maariv earlier before צאת הכוכבים, which means for this person it's Shabbos already, nevertheless you're not allowed to eat till צאת הכוכבים. So here we see that even though it's Shabbos already, nevertheless there's a possibility for the fast of Asarah B'Tevet to go into Shabbos, to extend itself into Shabbos. And on Shabbos, because to this person who daven Maariv it's Shabbos, on Shabbos he would be fasting the fast of Asarah B'Tevet. This shows how chamur, how strict the fast of Asarah B'Tevet is.

What is the reason for this? Why is Asarah B'Tevet such a strict ta'anit? So the reason bifshitut for that is because Asarah B'Tevet we fast because of the מצור on Yerushalayim. It is the day as the Rambam says in Hilchot Ta'aniyot פרק ה הלכה ב, taken from Tanach, in מלכים ב קפיטל כ״ה פסוק א וב, in ירמיה נ״ב פסוק ד וה, in יחזקאל קפיטל כ״ד פסוק ב, so from there the Rambam takes what he says that בו, in that day, meaning in עשרה בטבת, סמך מלך בבל. The מלך בבל leaned, which means surrounded, and he continues, על ירושלים והביאה במצור ובמצוק. And Nebuchadnezzar brought Jerusalem to מצור and to מצוק, which means into all the problems that happened. And since this was the beginning of the כללות concept of galut, because everything that happened later came after he surrounded Jerusalem. Later, on שבעה עשר בתמוז הובקעה העיר, that's when the city was broken. Tisha B'Av came the churban Beit Hamikdash, and then on the third day of Tishrei, or on Rosh Hashanah, that was when Gedaliah got killed. So all these בפשטות came as a המשך, as a continuation to what happened on Asara B'Tevet when Nebuchadnezzar made this מצור על ירושלים, made the siege on Jerusalem. So it comes out that the beginning of the חורבן בית ראשון, of the destruction of the first Beit Hamikdash, comes from Asara B'Tevet. That is the source of everything that happened later, including the churban Beit Hamikdash. And since we know that the churban of the second Beit Hamikdash and the galut that came as a result of the churban of the second Beit Hamikdash is a continuation to the churban of the first Beit Hamikdash, and not only that, in the second Beit Hamikdash the geulah was not a geulah sheleimah, it wasn't a complete geulah, as we see that in the second Beit Hamikdash five things were missing etc., so it comes out that Asara B'Tevet is also the beginning of the חורבן בית שני, of the destruction of the second Beit Hamikdash, and the galut that came as a result of the חורבן בית שני. Since the חורבן בית שני is a המשך to the חורבן בית ראשון, and even at the time of the בית שני the churban of the בית ראשון wasn't completely changed. So it comes out that עשרה בטבת is really the source of the חורבן בית ראשון and בית שני, and everything else that comes along with it. It's the source of the galut from בבל, it's the source of this galut, etc. And being that עשרה בטבת is the source of all the inyanim of galut and churban, therefore עשרה בטבת is stricter than all other taaniyot, even stricter than תשעה באב. And therefore the Abudarham holds that if עשרה בטבת comes out on Shabbos, if it would be able to come out on Shabbos, we would have to fast. And lehalacha lemaaseh we see that if it comes out on a Friday, we fast, and we even fast into Shabbos, even if the person would have davened Maariv earlier. To him it's Shabbos already, nevertheless he has to continue the fast of עשרה בטבת into the Shabbos. And this answers the kushya of the Lechem Mishneh on the Rambam in הלכות תעניות, where the Rambam says that the fast of עשרה בטבת is because of the siege of ירושלים by נבוכדנצר, so he asks: הוי לנו לשנותו ליום אשר סמך צר ידו על העיר בחורבן בית שני, דחמיר לן, that really we should have changed that fast day to the day when they surrounded ירושלים by the second בית המקדש, because that is stricter. As we find that we fast on שבעה עשר בתמוז, that's the day when the wall was broken, even though this happened in the second בית המקדש, because by the first בית המקדש the wall was broken on ט בתמוז, the ninth day of תמוז, but we fast on the day that the wall was broken in the second בית המקדש, because that is stricter to us and is closer to us, so he asks, the same thing should have been concerning the fast day that we fast because of the siege of ירושלים, it should have been when it happened in the second בית המקדש, not in the first. But based on what we said before, it's understood, because עשרה בטבת is really the beginning of everything. And therefore, when it comes to detail, the day that they broke the wall, so we say the day that they broke the wall by the second בית המקדש is closer to us and stricter, and therefore that's the day we fast. But concerning the siege of Jerusalem, being that this is the beginning, the beginning of everything, that is the beginning of the חורבן and the galut of the בית ראשון and בית שני, therefore that wasn't changed, and we still fast on עשרה בטבת, because this is very, very strict, being that this is the יסוד, the whole foundation of the concept of חורבן and galut.

Now, we know that the Torah gives us a klal, as the Gemara says in Megillah דף י״ג עמוד ב and in Midrashim, that הקדוש ברוך הוא מקדים רפואה למכה, that Hashem brings the refuah, the cure, before He brings the מכה, before He brings the disease, which means that before Hashem punishes the Yidden or does something bad, He beforehand shows them a way to get out of it, and a way to get teshuvah, do teshuvah, and in a way of curing that disease, so to speak. So from that, we understand that being that עשרה בטבת, as we said before, is a very, very terrible מכה, this is the source of all the ענין of galut, so therefore we must find something within עשרה בטבת which is the refuah before the מכה, which is the cure, and the teshuvah, so to speak, that Hashem put in to this terrible מכה of עשרה בטבת, of galut and חורבן. What is the refuah that we find in עשרה בטבת? This will be understood based on what the Gemara says in Yoma דף ט עמוד ב, that the reason for this galut, for this last galut which is lasting so long, till the Gemara says לא נתגלה קיצו, השם never revealed the end, when the end of galut will come, the reason is because of שנאת חנם, because there was hatred for no reason at that time. And being that this is such a terrible עבירה, so therefore the punishment for that עבירה is so that we don't even know the end to the galut. Now being that this is the מכה, the disease itself which brought to the galus is sinat chinam, so we have to understand that the רפואה, the cure to that מכה, is definitely the opposite of sinat chinam. And what is that? That is ahavat Yisrael, loving your fellow Jew, and not stam loving your fellow Jew, but ahavat chinam, loving him for no reason, just because he is a Jew. Just like the galus, which is the מכה, came because of sinat chinam, hatred from one Yid to another for no reason, so obviously the רפואה to that is not stam ahavat Yisrael, but ahavat chinam, loving another Yid for no reason, just because he is a Yid. And concerning the first Beis Hamikdash, even though we find in the Gemara that it wasn't for the reason of sinat chinam, but the Gemara gives the reason because of the three aveiros that they did, עבודה זרה, גילוי עריות, ושפיכות דמים, as the Gemara says there in Yoma, nevertheless, if there wouldn't have been some kind of lack in ahavat Yisrael, those aveiros would not have caused the churban Beis Hamikdash. As the Chazal say in the Midrash, in Bereishis Rabbah, פרשה ל״ח, ו', it says there that even if people do aveiros, and even if they do the worst aveiros, they do עבודה זרה, if they are be'achdus, no one could have any שליטה on them, no one could control them, no one could overcome them. As it was concerning the דור הפלגה, when they wanted to make the tower to fight Hashem, so they actually went out with a revolt against Hashem, nevertheless their punishment was not that they were killed. Their punishment was only that Hashem spread them out and changed their languages. Not like by the cheit of the דור המבול, that there Hashem actually killed them, even though their aveirah was not as great as the aveirah of the דור הפלגה, and the reason is because by the דור המבול there was no achdus. People robbed each other, there was no unity amongst the people, and therefore they were punished, they were died. But the people of דור הפלגה, even though their aveirah was greater, it was a מרידה in Hashem, nevertheless being that they were באחדות, they were all together, they were united as it says in the pasuk, therefore they were not punished in such a way. So from that we understand that even though the reason for the חורבן בית ראשון was not because of שנאת חנם, but it's self-understood that there was a lack in אהבת ישראל at that time, too. Because if there wouldn't have been a lack of an אהבת ישראל, so then even though they did עבודה זרה, גילוי עריות, ושפיכות דמים, but this would not have been enough to make the חורבן בית המקדש, because the fact that they would have been באחדות would have not allowed the punishment to come even for those aveirot. And being that they were punished, we must say that there, too, there was a lack of אהבת ישראל. And therefore, the refuah that has to come as a הקדמה to the מכה definitely has to be something within the inyan of אהבת ישראל. Where do we find, concerning Asarah B'Tevet, a concept, a remez, or an inyan of אהבת ישראל that was hinted in the inyan of Asarah B'Tevet?

So we find that in the lashon that it says concerning the siege that Nevuchadnetzar made on Yerushalayim, the lashon is סמך מלך בבל על ירושלים. The meaning of סמך really is from the word leaning, holding up, which is help, similar to the לשון סומך השם לכל הנופלים, השם holds up all those that fall, He helps those that fall. So as if it's saying here סמך מלך בבל על ירושלים, that the מלך of בבל held up and helped Yerushalayim. And the truth is, the Radak in his Sefer HaShorashim, ערך סמך, he writes that ענין השמות האלו is the inyan of משען, משען which means holding up, and he says ויש ענין קרוב לזה הענין, and he says there's an inyan which is similar to this inyan of holding up, and he quotes the פסוק סמך מלך בבל, and he says it comes from the word קירוב וסיבוב. So we see that the פסוק סמך מלך בבל על ירושלים also has a meaning of help. Now how did מלך בבל help Yerushalayim? How did he help the Yidden at that time when really what he did was he surrounded Yerushalayim in order to conquer Yerushalayim? But the emet is that when he made the siege on Yerushalayim, this itself was in one way the refuah before the makah. Because what is the concept of a מצור, of a siege? As the pasuk says אין יוצא ואין בא, no one from that city could go out, which means they all have to stay there together, and no one that doesn't belong there is able to come in, which means that people are all together. And also the nature of a siege is that when people are in a city which is surrounded by the enemy, everyone becomes friends. They all work with one common goal, try to save themselves and try to see that the siege should not be successful. So it comes out that when מלך בבל surrounded Yerushalayim, what he brought into the people of Yerushalayim was the feeling of achdus. And this is the deeper meaning in סמך מלך בבל על ירושלים, that the מלך בבל helped Yerushalayim. Since at that time there was a lack in achdus, so Hashem sent מלך בבל, Nevuchadnetzar, he should surround Yerushalayim, and when you surround the city in a way that everyone must stay there, and they all work together to save their lives and to help themselves, that is the inyan of achdus. And the truth is even more than that. Not only was it achdus concerning helping each other, etc., being that this was achdus within Yerushalayim, we know Yerushalayim is a place of kedushah. Yerushalayim is a place of yiras shamayim. As it says that the reason it's called Yerushalayim is it's a make-up of two words: yirah and shalem, which means complete yiras shamayim. So the achdus that took place in Yerushalayim is an achdus of yiras shamayim. So when the מלך of Bavel, Nevuchadnetzar, surrounded Yerushalayim, really it brought an achdus between them. So if the Yidden would have takeh utilized at that time, and would have actually become b'achdus even more, very strong, then takeh the end would have been that he wouldn't have conquered Yerushalayim. This was the refuah before the makah. But being that Hashem does not take away בחירה חפשית, the free choice, so unfortunately they didn't utilize this inyan of achdut properly, and therefore, as a result of that, what happened, that he did conquer Yerushalayim, and this was the beginning of the חורבן בית ראשון and later led up to the חורבן בית שני.

But now, when we come to Asarah b'Tevet, which is one of the fast days, the Rambam says the purpose of the fast days is to open the hearts to teshuvah, so we have to realize that what is really the refuah of Asarah b'Tevet is the inyan of Ahavat Yisrael, which came in the form of סמך מלך בבל על ירושלים. And if we want to get rid of the fast day of Asarah b'Tevet, and we want Asarah b'Tevet should turn into a Yom Tov, because all the fast days will turn in Yamim Tovim, and Asarah b'Tevet, which is the worst so to speak, will be the biggest Yom Tov, the way to do it is to strengthen our Ahavat Yisrael, and not only סתם אהבת ישראל because of a reason, but Ahavat Chinam, loving another Yid for no reason, just because he is a