I live in a predominantly Ashkenazic community where the “Three Weeks” are observed with no music, and certainly no celebrations or weddings. A Sefardic family in the neighborhood has scheduled a wedding during the Three Weeks.
The three weeks that begin on the night of the Seventeenth of Tammuz and continue until the Ninth of Av are days of national woefulness. The sages therefore advise being especially careful during this period, for it is a time designated for calamity.
Mourning the Temple's destruction must be internal. A person cannot simply jump into the Ninth of Av. One must enter it gradually in order that his mourning be earnest. Therefore, the intensity of our mourning over the Temple's ruin grows gradually.
The sages ruled that when a person builds a house for himself and arrives at its final stage, the whitewashing of the walls, he must remember that the Holy Temple still lies in ruins. He must therefore leave a square cubit of wall without whitewash.
If, during the Three Weeks, a person accidentally blessed "boreh pri ha'etz" over a new fruit, some authorities hold that the fruit should not be eaten. Others hold that pronouncing God's name in vain is a greater offense than eating the new fruit.
One disengagement leads to another, and those who disengage themselves from the past cannot bring us to our true future. Perhaps they can bring us to a Swedish or Luxembourgian version of the future, but not to the real destiny of the Jewish people.
The Chozeh of Lublin senses that the bed which has been prepared for him by the carpenter is not a rejuvenating bed but a bed of lugubriousness and anxiety. From such a bed it is impossible to rise invigorated with a thirst for renewed creativity.
The Three Weeks between the 17th of Tamuz and the 9th of Av are a time of sadness and danger. Rav Kook shows that they are also a time during which we can rebuild the Temple if we learn the secret of Causeless Love.
: In mourning over the Temple, we refuse to come to terms with the destruction. We begin with a life in which the Temple plays no role, and, in stages, return to the feeling of "one's dead lying before him."
It is forbidden to use arrogance in a contemptuous manner, placing oneself above others, yet there are certain situations in which one has to be bold, not reserved, and to know one's self-worth. Our sages teach that in the generation of the messiah chutzpah will abound.