Musar su Genesi 31:40

Aba Chilkiya did not even return the greetings of Torah scholars in order to not be idle from the work he was doing for another (Taanit 23b). Yaakov, our forefather, peace be unto him, states explicitly, "in the day heat consumed me, and the frost by night, and my sleep departed from my eyes" (Bereishis 31:40).

For after a person has truly understood the obligation of Cleanliness and its necessity, having already attained Watchfulness and Zeal by engaging in the means they are acquired and distancing from their detriments, behold, he will no longer have any more obstructions preventing him from attaining Cleanliness except knowledge of the fine details of the Mitzvot in order to guard himself in all of them.

Also, since one is prone to forgetfulness in these fine details, he will need diligent study in the books explaining these fine details to renew remembrance of them in his mind. Then certainly, he will be roused to fulfill them.