לקוטי שיחות חלק י״ט - כי תצא ב

On the verse, “When you build a new house, you shall make a parapet for your roof… lest the one who falls fall from it,” it must be understood why the verse says “a new house,” since the mitzvah of making a parapet applies to every house.

This matter cannot be fully understood according to the revealed dimension of Torah alone. It is specifically through the inner explanation that it can be understood. This itself demonstrates that even the revealed dimension of Torah, although it is clothed in human intellect, is essentially Divine wisdom.

The explanation is as follows:

“A new house” refers to the avodah at the beginning of married life. At that point begins the primary avodah of making a dwelling for Hashem in the lower realms. This avodah is called a “new house” in the sense of something novel, and this avodah brings about an incomparable new development within the person who performs it.

This avodah involves a descent into the lower realms — “lest the one who falls fall.” Therefore, the command is that a person must make a parapet: new safeguards and boundaries in the service of Hashem, so that he should not fall downward.

The parapet also teaches that even when a person descends into involvement with lower matters, he must remain separate from those lower matters, because his entire involvement with them is for the sake of the Holy One, blessed be He.