In the wake of recent world events, such as the tragedy in Mumbai, the idea of reciting psalms (or performing a mitzvah) on behalf of another person has spread worldwide. And, accompanying the request, the Hebrew names of the person for whom the psalms are being recited (or the mitzvah performed) are always included.
In general, the person's name is accompanied by their mother's name, for example, Iaacov ben Rivka.
However, when it comes to a ceremony in memory of someone who has died, the name used is the name of the father, for example, Iaacov ben Itzjak: Why? And, furthermore, what does this tell us for our daily lives?
Our sages explain that human beings have two fundamental components: soul and body. One without the other cannot fulfill its purpose. The soul without a body cannot express itself in this physical world and transform it into a dwelling place for God, and the body without the soul cannot live.
This union of soul and body is so profound, to the point that two components are not distinguished in each person; one does not see a body plus a soul, but rather a "living body".
Now, the father is the one who provides the son (or daughter) with the innermost component, so to speak, the soul's relationship with God. The mother provides the outermost component, so to speak, the soul's relationship with the body.
So, when we pray for someone's well-being and health, we use the mother's name, because that name specifically relates to the person's physical needs. Whereas, when we pray for the elevation of a deceased person's soul, since the connection to the body is no longer there, we pray using the person's name plus the father's name.
The teaching of this idea is very simple: the nature of man and woman are very different: man tends to be linked to spiritual matters, to fly through the skies of meditation and transcendental, while woman tends towards the earthly, as people say, "has her feet on the ground".
That is why the Torah only calls them "Man" when a man and a woman are united.