Rashi (according to the metaphor): He constantly reviews his learning, lest he forget it.

Malbim: One who works his land, even though man's nature leans towards rest and not working, and the land needs to be worked

R. Yonah: This expands on "Tov Nikleh v'Eved Lo" (9). One who considers himself honored and refrains from working due to his authority, and he has no money or merchandise to deal with, and he joins with empty people who are idle from work, he is Chaser Lev. This is more than merely Chaser Lechem - idleness brings to insanity (Kesuvos 59b). Also, perhaps he will learn lowly Midos from being amidst empty people - "Pen Te'elaf Orchosav" (22:25).

Malbim: One who pursues ¹ to get his income via rest and not working his land, he is Chaser Lev. He has no power that rules to rebuke laziness via seeing the consequences. It says below "Meradef Reikim Yisba Rish;