Lines in a Sefer Torah

There are various opinions as to how many lines there should be on a regular page of a Sefer Torah and to what they correspond. The Tur (יו"ד סי' ער"ה) brings different customs, stating a range of 48 (corresponding to the journeys of the Jews in the desert) to 60 (corresponding to the 600,000 Jews). He then brings the opinion of R. Yehuda of Barcelona that it should be 42 lines corresponding to the word “בם.”
The principle source for the number of lines is the “small” Mesechta of “Sofrim” which mentions that it should be 42 lines corresponding to the journeys of the Jews in the desert. The source of the Tur who mentions that it should be 48 lines correspondent to the same thing is from a responsa of the Mahara”m of Rothenberg. This begs the question – if the source says 42 lines, and looking in the Torah one will see that this is indeed the case, how could he say that it’s 48 lines/journeys?
It must be that the Mahara”m is including the travels the Jews did in retreat after Aharon's death, which are technically not counted as part of the 42.
פרישה יו"ד סי' ער"ה סקי"ג-י"ד

Seudas Mitzvah by a Bris

One should make a festive meal by a Bris Milah. The Rama"h writes that this meal is called a seudas mitzvah (רמ"א יו"ד סי' רס"ה סי"ב). As such, it should be celebrated appropriately, with a befitting repast; preferably with meat. There are Poskim that rule that if one does not serve meat, he has not fulfilled his obligation. (מג"א סי' רמ"ט סק"ו ובמחצית השקל שם).
R. Avraham Yehoshua Heshel of Apta, know as the "Apta Rov" and author of "Ohev Yisrael" noted that people were lax in this and sufficed with serving only coffee by the Bris Milahs they would make. He remarked "I don't see how an appropriate child will grow from the coffee-bris..."
ברית אבות סי' י"ג אות א
ועי' מגדל עוז (יעב”ץ) נחל התשיעי יאור י”ז אות ג
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Al Naharos Bavel Before Bentching

The Zohar (קנז, ב) states that one who partakes of a meal and enjoys the food should remember the holy land and the destroyed Temple. Therefore, the wide-spread custom is to recite the Psalm "On the banks of the rivers of Babylon..." which mourns the destruction of the Temple prior to reciting Birkas Hamazon. (מג"א סי' א' סק"ה)
Now, this custom is - as its title indicates - is not more than a custom. However, R. Moshe ben Machir, 16th century sage of Tzfas, in his famous work "Seder Hayom" shares an allusion to this idea from the chapter in Tehillim itself: The chapter that directly proceeds it contains the following words near its conclusion "He who gives bread to all living beings." It is reasonable that the following chapter of "On the banks of the rivers of Babylon..." should be juxtaposed to Birkas Hamazon which is recited over bread.
סדר היום ריש זכר החורבן וחיבו הלמוד בשעת אכילה וסדר ברהמ"ז
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What's the Definition of "Beauty"?

The Kohen Gadol was supposed to be the "greatest of his brethren," surpassing them in - as the Rambam writes - "beauty, power, wealth, wisdom, and appearance."
Defining the exact difference between "beauty" and "appearance," R. Yosek Korkos writes a brilliantly detailed description of what beauty and charm mean:
"'Beauty' is the beauty of the face while 'appearance' is the [general] beauty of the entire being, what in our language is called 'presence.' This is also [a reference] to the charm of his figure, for there are people with a beautiful figure yet they do not charm their viewers, nor do they have a majesty to their face, and they do not impose fear upon those who behold them."
מהר"י קורקוס לרמב"ם מהל' כלי המקדש ריש פ"ה
ועי' במשרת משה (עטייה) על הרמב"ם שם שמפרש ע"פ הפסוק גבי יוסף יפה תואר ויפה מראה, ע"ש

Is a Convert Really a New Person?

A well known rule is the rule of the convert: "גר שנתגייר כקטן שנולד דמי - a convert is like a newborn child." (יבמות סב, ב. ובכ"מ) A practical halachic application of this is the din that according to the Torah, a convert may marry his former siblings, as they no longer have any genealogical ties. Only the Rabbis prohibited it. (שו"ע יו"ד סי' רס"ט ס"א)
The Chasam Sofer (חידושים על הש"ס ע"ז סה, א ד"ה אקילו ביה רבנן) writes that "I toiled very hard, yet have not found the source from where the Rabbis deduced this and Biblically permitted a convert to marry his siblings..."
Well, here's an idea: When the Jews told Moshe that they cannot handle hearing the word of G-d directly from Him and requested Moshe to be their intermediary, Hashem aceded to their requested stating "Go and tell them 'return to your tents.'" (דברים ה, כז) Now, a "tent" is a home, or in Talmudic terms, the wife. Hashem was telling them to return to their wives from whom they had separated for the duration of the Giving of the Torah.
These wives were not necessarily permitted by Biblical law. Why, Amram - Moshes's father - was married to his aunt! Yet, Hashem instructed the Jews to resume matrimonial ties with these women. From here we see that a convert - as the Jews were after receiving the Torah - is like a new man and permitted to marry his kin.
משך חכמה דברים ה, כז
ועי' בלבוש יו"ד ריש סי' רס"ט "אמרו חז"ל הדעת נותן" שמדבריו משמע שהיא מסברא, וצ"ע
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Threefold Blessing

The Birchas Kohanim mentioned in the Torah "יברכך... יאר... ישא" is referred to as the "ברכה המשולשת - the threefold blessing." The simple explanation thereof is due to its composition of three pessukim which contain three distinct blessings.
Another interesting way of looking at it: The Gemara (ברכות ח, א-ב) says that a person should read the Parshah twice in Hebrew and once with Targum (Aramaic) "even the words עטרות ודיבן." Rashi explains that these words do not have an Aramaic translation. Indeed, the halachah states that such pessukim should be read three times in Hebrew, the third time in Hebrew replacing the missing Aramaic. (שו"ע סי' רפ"ה ס"א ובמשנ"ב שם סק"ג)
In light of the above, we can easily understand why the pessukim of Birchas Kohanim are labeled "threefold," for they have no Aramaic translation. Thus, we read them in Hebrew three times.
הקדמת בן המחבר דשל"ה הקדוש "עמוד השלום" פכ"ו
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Temporary Mezuzah

If one checks their mezuzah, do they need to put up another one in the interim?
Depends: If one will be checking their mezuzah right away and is actively working on getting it checked, he need not put one up in the meanwhile. If, however, one is concerned about the kashrus of his mezuzah and took it down and is waiting to get it checked (like in days of old that one would wait for a traveling scribe to pass through the village), it depends: if he owns the house, he should put one up; if he rents and it is outside the land of Israel, he could be lenient.
דעת קדושים (מבעל האשל אברהם) סי' רצ"א ס"ב
וכן נפסק בספר "חובת הדר" פ"א ס"ח
ועי' בספר עלי דשא (שפירא) סי' ל"ג עלה ט שדן בזה
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