Late Friday afternoon, 40 minutes before the sunsets, a siren sounds throughout Jerusalem announcing that it’s time to get ready for Shabbat. At that moment, many in the city light their candles. Some wait until 18 minutes before Shabbat. Some don’t observe Shabbat at all. But, no matter what your religious practice is or isn’t, when that siren sounds, you can feel the energy shift in Jerusalem. Things slow down. It gets quieter. 2,500 years ago, long before the invention of the Shabbat siren, a shofar was blown from the Temple in Jerusalem to announce the arrival of Shabbat. The Talmud explains that six shofar blasts were sounded over a period of time late on Friday afternoon. Each blast was designed to get the people ready for the day of rest. The first blast, the Talmud says, was to tell people to cease work in the fields; the second blast,…