When Jews wish to congratulate other people, they usually exclaim in Hebrew “Mazal Tov.” I am glad we do not dwell on the literal meaning of these words, because if we did, most of us would not say them at all. But words change meaning, and “Mazal Tov” is one of them.
Literally, “Mazal Tov” signifies “good fortune.” In Hebrew, “Tov” means “good” and “mazal” (pl. mazalot; from the Akkadian mazaztu or mazazu) is an astrological expression, referring to the heavenly constellations or the stars in the zodiac, which presumably have influence on human beings and, in fact, determine their destiny. So, when we wish others “Mazal Tov,” we are hoping that the stars will be favorable to them.
Traditional Jewish texts reflect an ambivalent attitude regarding astrology. Many Biblical texts consider it of foreign origin. Thus, for instance, some prophets scoff at “star-gazers” (cf. Isa. 47: 13; Jer. 10:2) among the nations, and biblical law prohibits the practice of divination and soothsaying (Lev. 19: 26; cf. Deut. 18: 10) among the Israelites. But the practice must have been extensive in ancient Israel, even in the holy temple, for in the 7th cent. BCE, King Josiah of Judah suppressed the priests who made offerings “to the sun, moon and constellations (mazalot)” (II K 23: 5). On the other hand, Job states that it is God who sets the stars (here called mazarot in 38: 32) in their courses.
Post biblical literature knows of astrology but presents a mix bag. While the Book of Enoch (2nd cent. BCE) considers it a sin (8: 3), the Jewish historian Josephus tells us that it was very popular among Jews (Wars, 6: 288f). The Talmud, too, is ambivalent about the subject. Though the majority of the Rabbis argued that God established the constellations (see, BT Ber. 32b) and that each human being is under the influence of the planets ( BT Shab. 53b), Rabbi Johanan maintained that “Israel is immune to planetary influence” (BT Shab. 156a).
During the medieval times, most Jewish philosophers supported astrology, but Moses Maimonides (12/3th cent.) considered it a superstition (Yad, Avodah Zarah, 11: 8-9). Another Jewish philosopher, Hasdai Crescas (14/15th cent.), too, argued that it is impossible to attribute a decisive character to the dictates of the star configurations (Or Adonai 4: 4). On the other hand, the Zohar, the main texts of the Kabbalah, took astrology for granted. In the glorious days of Spanish Jewry, a number of Jewish scholars wrote books on astrology, and defended its practice.
Today, a number of people begin their day by checking their horoscope, and make important decisions based on these predictions. To me, this is pure superstition and borders on idolatry. However, I am not willing to give up the practice of wishing someone “Mazal Tov,” because of its past meaning. Presently, for most people, this expression is devoid of its original intent, and simply means, “May it be well with you.” I can drink to that.
So, Mazal Tov, to all of you.
PS. There a good article on “Astrology” in the Encyclopaedia Judaica (2007, Vol 2, pp.616-620) by Alexander Altman, which also appears in the Jewish Virtual Library.