Tammuz is the fourth month of the Jewish calendar. Tammuz begins the summer season. It is a challenging season for the Jewish people. Each month of the year is governed by another combination of the four letter name of G-d; the name that governs the month of Tammuz is ה-ו-ה-י, which is the opposite order of the way G-d's name is usually written (י-ה-ו-ה). This, according to Kabbalah, alludes to the Midat Hadin - the attribute of judgment. The three months of summer: Tammuz, Av, and Elul, begin with the challenge of severity and judgment, but end with the gift of teshuvah (return, often translated as repentance) and rachamim (mercy).The letter that is crowned in the month of Tammuz is the letter Chet (ח) which means sin in Hebrew. Tammuz is the month of the sin of the golden calf, which resulted in Moses breaking the tablets that held the ten commandments. The day of the breaking of the tablets - the 17th of Tammuz - begins the three week period (Bein Hameitzarim) which commemorates the time leading to the destruction of the Holy Temple in Jerusalem. That period began with the breaking through of the wall surrounding the holy city and culminated in the destruction and burning of both Temples (in different eras) on the ninth of Av.
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