Each Shabbat evening we turn toward the door during “Lecha Dodi” to greet the “Sabbath Bride.” This tradition harkens back to the hills of 16th-century Safed and reminds us that Judaism cherishes what we cannot see.

We are surrounded by certainty. After a lifetime of finding out how wrong I can be about things I used to be sure of — including myself — I am amazed by the tub-thumping certainty of people around me. From politicians to pundits to preachers to — well, everyone — people seem incapable of entertaining the possibility they may be wrong. No wonder the Talmud tells us, “Teach your tongue to say ‘I don’t know.’”