I am not Jewish, but I frequently hear the words "Mazal Tov" at a wedding or on television. What is the origin of this expression?
The Aish Rabbi Replies
Mazal is the astrological influence that a person is born under. The Talmud (Shabbat 156a) discusses what has a greater influence on a person: the day of the week (with attributes based on the days of creation), or the planetary sign. This influence is a spiritual flow that God has set into creation (and it is not any independent power, God forbid).
That is why we wish people "mazal tov" - literally that they should have a "good mazal."
On the other hand, the same piece of Talmud states the concept of "ain mazal l'Yisrael" - that Jews are not bound by any astrological influence, and are able to override any predetermined astrological pattern.
In Jewish thinking, a person's whole future is mapped out in the stars, and for one who knows how, reading the stars is like reading a book of the future. It is, however, forbidden for a Jew to read the stars or listen to someone who can do so. The Torah tells us that God took Abraham and lifted him "above the stars." Abraham was able to have a child at age 100, with his 90-year-old wife Sarah that had no womb! A Jew, God told Abraham, should be "above the stars." The message is that the stars would have no influence on Abraham or his future descendents.
The Talmud cites the example of Rebbe Akiva's daughter, whose mazal indicated that she would die young. However, the tragedy was averted by her involvement in Torah and mitzvot, specifically doing kind deeds. (At her wedding celebration, she took time out to tend to the poor people; the snake that was destined to bite her was killed instead.)
By elevating herself, she literally changed her human nature, and thus the original mazal-influence no longer applied.
Our horoscopes are only as true as we allow them to be. Unfortunately, it is much easier to go through life on automatic pilot. Life can go where the stars say it will, or where we want it to go. The choice is entirely ours.
So you see, while we wish people good "mazal" (i.e. their "default" influence from above), we also strive to change and improve that influence.