One of the most sacred rituals which has been faithfully observed by all Jews throughout the generations is the practice of reciting Kaddish at the three daily prayers during the year of mourning. Halachah rules that we begin saying the Kaddish at the time of burial and continue until the conclusion of the eleventh month of mourning. The exact day on which we conclude saying Kaddish depends on diverse customs, and in Lubavitch our custom is to conclude the recital of Kaddish one day before the end of eleven months.1

In discussing this practice of interrupting the Kaddish before the end of the year, the Ramo writes in the Code of Jewish Law:

The judgment of wrongdoers (after death) lasts for 12 months and we do not want to suggest that our departed relative was a wicked person2.

This explanation of the Ramo is based on the concept that the recitation of Kaddish by the mourners helps the soul of the deceased in its heavenly judgment.

We follow this common practice for all Jews since every Jew has the presumption of righteousness (see Rambam, Laws of Sanctification of the New Moon) as the prophet declares, “Your nation are all righteous3.” This is true even in the case of Jews who were known to have sinned and certainly so in the case of the righteous.

We may further suggest, based on the reason just given, that in fact the cessation of the Kaddish is not merely an external show of respect, rather it has a real positive effect. When we proclaim our faith in the righteousness of the deceased it helps to neutralize any negative heavenly judgment so that the soul of the departed will be able to ascend to the realm of paradise.

This concept was expressed by the authors of the Midrash:

For when a man departs from the world, the Holy One, Blessed be He, says to the ministering angels: ‘See what his fellow-men are saying about him.’ [If they say] that he had been right-living and G‑d-fearing, his bier at once flies up into the air (his soul ascends to heaven)4.