The Yismach Moshe explains:
Doing a חוק—a mitzvah for which the reason is not given but we must simply carry it out without understanding—distances a person from mosros, from gashmiyus. And the reason is as follows: When a person carries out mitzvos—without deriving pleasure from the meaning of the mitzvah, doing them simply because Hashem commanded him to do so—such a person is subjugating himself to the Ribbono shel Olam, and he removes from himself the ta’avah for unnecessary gashmiyus.
For pursuing mosros (literally, extras) means that one’s soul is searching constantly: “What can I gain? Where can I benefit? What can bring me parnassah? Which segulah can I do for money? What can I do for stature or shidduchim?” Such a person will also seek mosros—because this is what brings him pleasure in that moment. Such a person enjoys lomdus, but he also likes a good steak; he appreciates a nice pilpul, but he also enjoys a good lashon hara, R”l. When it comes to mitzvos that he doesn’t “connect with” as much—there he will exert less effort. Such a person will seek pleasure in foreign places...because at the end of the day it is all about himself and his pleasure.
When a person fulfills חוקים—and we see this in different kehillos or chassidic groups where there are expectations or minhagim about which it is said, “This is what we do here...” with no reason given (for example, in some places the davening takes longer, some places have the minhag of traveling to the Rebbe)—the person doesn’t necessarily find pleasure in them—but this is what is done... no questions asked: It is specifically these aspects of avodas Hashem that peel away the ga’avah—because he makes his avodah about Hashem, not about himself—and if the ga’avah is removed, HaKadosh Baruch Hu is closer to him, and he merits success and closeness to Hashem.
