Musar על אבות 6:5

But since he cannot bear to see himself lower and lesser than his peers, he puts himself squarely under the thickness of the beam. Thus there is no end to all his labor. Therefore, our Teachers, of blessed memory, taught us "jealousy, lust, and honor remove a person from the world" (Avot 4:21), and warned us: "do not seek greatness for yourself, and do not lust for honor" (Avot 6:5).