Hot answers tagged three-weeks
Shulchan Aruch Orach Chaim 551:17 says: טוב ליזהר מלומר שהחיינו בין המצרים על פרי או על מלבוש אבל על פדיון הבן אומר ולא יחמיץ המצוה It is good to avoid saying Shehechianu in the three weeks on a fruit or clothing, but on a Pidyon HaBen he says it and doesn't postpone the Mitzvah. The Magein Avraham (s.v. ולא יחמץ המצוה) quotes the Maharil as saying ...
The Rama himself actually forbids haircuts starting on the 17th of Tammuz (ShA OC 551:4). In his Darkei Moshe, he cites Minhagim Tirna on Tammuz (written ~1400 CE) which mentions this custom.
All surgery that can safely be postponed until after Tisha B'Av should be postponed. See R. Simcha Bunim Cohen's Halachos for Daily Living, volume on the Three Weeks and Fast Days. Published by ArtScroll.
Shulchan Arukh, Orach Chayyim 551:6: כלים חדשים בין לבנים בין צבועים בין של צמר בין של פשתן אסור ללבוש בשבת זה ( ואנו מחמירין מראש חודש ואילך): New clothes, whether they are white or colored, whether made from wool or flax are forbidden to be worn on this Shabbat (and we are stringent not to do so from Rosh Hodesh Av onwards.) See Magen Avraham ...
The Three Weeks are those days between 17 Tamuz, when the walls around Yerushalaim were breached by Titus's army, and 9 Av, when the Bais Hamikdash was actually destroyed. It would have been a period of heavy fighting, more than just a siege. As to your second question: The Gemara (Tanis) doesn't mention a mourning period starting from 17 Tamuz. It's an ...
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