Shmuel Hanavi's Hairstyle

The name of the father of the navi Yoel written in Tanach is “פתואל.” The Midrash (ילקוט שמעוני יואל רמז תקל"ג) writes that this was actually the navi Shmuel. Why was he given this name? One of the reasons is that it’s similar to the word “בתולה – a young girl,” and Shmuel would comb his hair like a young girl.
Now, why would Shmuel comb his hair like a girl?
Shmuel was a nazir. Being that even a Yisrael is not allowed to enter any part of the Mishkan with long and unruly hair, Shmuel was required to comb it and make it look nice so he should be allowed to enter the Mishkan in Shiloh which he frequented.
אור שמח על הרמב"ם הל' ביאת המקדש פ"א הי"ז
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Throwing Away Papa's Money

The Gemara (סנהדרין כב, ב. נדרים נא, א) tells us of a certain "Ben Eleasa" who would spend large sums of money in an effort to learn the unique hairstyle that the Kohen Gadol had in the Beis Hamikdash. The Gemara comments that this effort was "not for naught."
Why would the Gemara feel it necessary to inform the reader that it wasn't for naught - what would prompt one to think that it was?
The Maharsh"a explains: Let us examine this man's name - "Ben Eleasa." Why was he given this name; if he was indeed a wealthy and important man, why did he not merit to be addressed with his own given name? The answer is that this man did not accumulate his own wealth, rather he inherited it from his father. As such, his entire legacy was attributed to the owner of his money - his father.
Now, people in such a position usually squander their money as they do not appreciate its value. Therefore, the Gemara tells us that this man did not do that; "not for naught" did he expend large sums of money, for his motives were noble, as he was trying to learn about the ways of the Kohen Gadol.
מהרש"א חדא"ג נדרים נא, א ד"ה מאי בן אלעשה

Mechitzah - a Modern Invention?

Walking into any Orthodox Shul today, you will encounter a mechitzah, a partition running between the men and ladies section of the Shul. Others have a separate balcony for the ladies. One may wonder why is the mechitzah never mentioned in Shulchan Aruch or other earlier seforim? Why was this only recently discussed, and with such passion, by the great Rabbis of a more modern Europe?
The answer is simple: up until modern times, the style of the Shul was completely different. Women that wished to come and daven would sit in a completely separate room and would only hear the sounds of the davening by way of small windows.
שו"ת ציץ אליעזר ח"ז סי' ח
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Gid Hanashe and Fast Days

When Yaakov was left alone to retrieve his jugs, he got embroiled in a fight with the angel of his evil brother Esav. They battled all night long, and upon seeing dawn on the horizon, the angel gave up, but not without striking Yaakov on the thigh and injuring him. Because of this, the Torah says that "על כן לא יאכלו בני ישראל את גיד הנשה - therefore, the Jews do not eat the gid hanasheh, the sciatic nerve."
Homiletically, this passuk can be interpreted to be referring to the days of the year when Jews "do not eat" at all, the public fast days:
The passuk reads as follows: "Therefore the Jews do not eat [on the days hinted to in the following words]:
"את - the ninth (תשעה) of the month of Av (אב);
"גיד - the 3rd (ג) day of the month of Tishrei;
"גיד - the 10th (י) day of the month of Teves;
"גיד - the 17th (the gematriah of גיד) day of Tammuz."
ש"ך על התורה בראשית לב, לג בסופו
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The Arizal and the Eruv

R. Chaim Vital writes of his esteemed master and teacher, the Arizal, that he was careful to make an eruvei chatzeiros every week before Shabbos, not like those that suffice with making one for the entire year. Indeed, the Arizal was very into the eiruv of his city, the fabled mystical town of Tzfas. Says R. Chaim Vital:
"I saw that my master would carry his tallis and chumash on Shabbos morning from his home to Shul. He would also carry it to the famous mikvah outside the city and he was not particular, nor did he bother, to verify if the eiruv for all the alleys of the city of Tzfas aw well as for the mikvah were made according to halachah."
שער הכוונות להרח"ו ז"ל ענין רחיצת פניו ורגליו ד"ה ענין העירוב
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Three Signs of a Scholar

The Gemara (חולין ט, א) declares that a Talmid Chacham must know three things: ksav (writing), shechitah, and milah. Rashi (ד"ה כתב) explains that "ksav" means the simple knowledge of writing, for the scholar should know how to sign his name were he to sit as a judge or a witness.
Explaining why it doesn't mean the knowledge of the laws of writing a Sefer Torah etc., the Maharsh"a explains that the Torah scholar's knowledge of all areas of halachah is a given; this cannnot be what the Gemara means when it says that he must be knowledgeable in "writing." Rather, the intent is the skill of signing his name.
Alternatively, the intent is the obligation a Talmid Chacham has to "transcribe" his Torah thoughts. One whom Hashem has bestowed with the wisdom to expand Torah knowledge is obligated to do so lest it be forgotten. Should he not do so, it is tantamount to spilling seed in vain.
פי' רוב דגן (עטייה) לחולין ט, א ד"ה ח"ח צריך שידע
ועי' בספר אברהם את עיניו(פלאג'י) למס' זו פי' יפה
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Forced Marriage, Can't Get Rid of Us

The Gemara (שבת פח, א) relates that when Hashem approached the Jews with the proposition of receiving the Torah, He was rather forceful about it. He suspended a mountain over their heads and asked them if they would accept it; if not, then and there would be their burial.
Why did Hashem choose such an interesting manner to give the Torah to His beloved nation?
Giving the Torah at Mt. Sinai was the wedding day of the Jewish people with Hashem (תענית כו ,ב). The halachah states that a person who forcefully marries a woman is obligated to remain married to her (if she so wishes) and, unlike all other marriages, is never allowed to divorce her. Were he to give her a get, it is invalid.
Hashem foresaw that His "wife-to-be," the Jewish people, just may end up in trouble and warrant a "divorce." This He did not want; so, He "forcefully" married them, thus disabling a divorce forever.
צפנת פענח חדש ערך נשואין וגירושין אופן הא
ועי' בגור אריה שמות יט, יז פי' דומה
ועי' לקוש ח"א שיחה ב' לפ' תצא
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