Kaddish, a Memorial Prayer in Praise of God

The Kaddish is recited in a prayer service, on a daily or weekly basis, after the death of a close relative.

By Rabbi Joseph Telushkin

Reprinted with permission from Jewish Literacy (HarperCollins Publishers Inc.).
Throughout [Jewish Literacy], I have generally tried to be descriptive rather than prescriptive. However, when it comes to reciting the Mourner's Kaddish, I feel compelled to urge my readers, "Do it."
The Kaddish, an Aramaic prayer that is [almost] 2,000 years old, is recited in slightly different variations at every prayer service. Although one form of the Kaddish is recited in memory of the dead, the prayer itself says nothing about death; its theme is the greatness of God, reflected in its opening words: "Yitgadal ve-yitkadash, Shmei rabbah--May His name be magnified and made holy…. " The prayer's conclusion speaks of a future age in which God will redeem the world.
Why then was this prayer designated by Jewish law to memorialize the dead? There is no definite answer; the tradition dates only from the Middle Ages. Most likely, people believed that the finest way to honor the dead was to recite the Kaddish, thereby testifying that the deceased person left behind worthy descendants, people who attend prayer services daily and proclaim there their ongoing loyalty to God.
Reciting the Kaddish also forces mourners to go out in public. After the death of a loved one, a person might well wish to stay home alone, or with a few family members, and brood. But saying Kaddish forces a mourner to join with others. According to Jewish law, the Kaddish cannot be recited unless a minimum of 10 adult Jews are gathered in a minyan [quorum for prayer].
Because of the Kaddish's therapeutic value, I believe it is important that it be recited by women as well as men. Throughout Jewish history, only men had the obligation to say the Kaddish. So associated was this prayer with men that Eastern European parents sometimes referred to a son as their Kaddishl--the one who would recite Kaddish for them. Among traditional Jews, it was considered disadvantageous to have only daughters, because there would be no child to say Kaddish after the parents' deaths.
However, even before the rise of feminism, there were Jewish women who said Kaddish. A gem of modern Jewish literature is a letter written by Henrietta Szold, one of eight daughters of a Baltimore rabbi and a great figure in American-Jewish history. When Szold's mother died, a close male friend of the family, Haym Peretz, offered to say Kaddish on her behalf. An excerpt from the letter in which Szold refused his offer, insisting that she would say the Kaddish herself:
"I believe that the elimination of women from such duties was never intended by our law and custom--women were freed from positive duties when they could not perform them [because of family responsibilities] but not when they could. It was never intended that, if they could perform them, their performance of them should not be considered as valuable and valid as when one of the male sex performed them."
Kaddish is recited every day during the morning, afternoon, and evening services. Ideally, one should attend every service, but if one cannot do so, it is desirable to attend at least one of the three daily services. In the observance of Kaddish, as in most areas of Jewish life, something is better than nothing. If it is impossible to attend a daily service, then one should at least say the Kaddish on the Sabbath.
In the case of the death of a sibling, a child, or a spouse, Kaddish is recited for one month; when a parent dies, it is recited for 11 months. The reason the Kaddish is said for 11 months, although the full mourning period lasts for 12, has to do with folklore. According to a statement in the Talmud, when the most wicked people die, they are consigned to hell for a maximum of 12 months. Since recitation of the Kaddish is believed to help elevate the soul of the dead (see Sanhedrin 104a), reciting it for a full year would imply that one's parent is one of those wicked people sentenced to a full year in hell; hence, the Kaddish is recited for only 11 months.