What is a Jewish Birthday?

You can wish the celebrant a successful and productive year, and because their spiritual abilities are particularly strong that day, you can ask to be blessed in return.

The source for this is Jerusalem Talmud 3:8. There we read that Israel’s enemy, Amalek, chose warriors to fight on their birthday, figuring that a man would not fall in battle on a day when his mazal was dominant. What did Moses do? He “mixed up the mazalot” so that their mazalot were not in effect.

What does it mean that a person’s mazal rules on the day of his birthday? Each of us has a specific spiritual source from which we come and we draw our sustenance. On a person’s birthday, this is particularly strong—increasing his or her abilities.

In a letter, the Lubavitcher Rebbe advised that a convert celebrate the day that he/she became Jewish as his/her birthday.

First of all, I want to let you know that you share your birthday with someone very special.

As you know, the saddest day on the Jewish calendar is the 9th of Av, the date when – among other tragedies – both Holy Temples were destroyed, leading to our nation's exile from the Holy Land. Nevertheless, our Sages tell us that despite the sadness and pain, this is the birthday of Moshiach, our future redeemer:

"On the day that the Holy Temple was destroyed, a Jew was plowing his field when his cow suddenly called out. An Arab was passing by and heard the low of the cow. Said the Arab: 'Jew, Jew! Unyoke your cow, free the stake of your plow, for your Holy Temple has now been destroyed.' The cow then lowed a second time. Said the Arab: 'Jew, Jew! Yoke your cow, reset the stake of your plow, for the Redeemer has now been born...'"

The redeemer, and with him the potential for redemption, was born the moment after the destruction. So being born on this day is nothing to feel bad about.

I would suggest that while you spend your actual birthday in contemplation and spiritual introspection, you have your birthday celebration—with food, friends and Torah thoughts—a day or two after your actual birthday.