Q. Do Jews take astrology seriously?
Ancient monarchs thought astrology was a science, and their courts had their official astrologers. Even King Solomon is said to have believed in astrology, and some of the rabbis took it seriously, though others called it a gentile and not a Jewish practice.
Rabbi Yochanan said, Ein mazal b’yisra’el – “Jews do not believe in planetary influences” (Talmud Shabbat 156a). Maimonides regarded astrology as mere superstition and argued that to believe that the heavenly bodies influence your life undermines the power of free will.
The prophet Isaiah mocked the resort to astrology and sarcastically told the Babylonians that if they feared destruction they could consult the astrologers and see if the stars could help (Isa. 47:13).
Not that the Bible or Judaism lacked respect for the heavens. The Psalmist tells us that the heavens “declare the glory of God” (Psalm 19:1), but observing the heavenly bodies was not for the sake of homage but to see the greatness of the Creator and to know that He who implanted the heavenly bodies was the director of destiny.
The great 3rd century rabbi, Samuel, was said to have known the pathways of heaven as well as he knew the streets of his own town (Ber. 58b), but he and other sages watched the skies as part of their mathematical and astronomical studies, especially in order to work out calendrical principles.
Some of our medieval and later forebears did take astrology seriously and were sure that the stars influenced one’s personal life and prosperity.
To this day the most rational of people wish one another Mazal Tov, literally “a good planet”, but no-one takes the greeting literally.