Chazal say: Rebbi wept and said that one can acquire his future world in one hour while others take years to attain theirs. The Maharsha writes: Rebbi wept over the lesser worth of one who gains his Olam Haba in merely an hour as compared to the one who toils for it over a long period, but whose input gains him a far worthier place commensurate with his greater effort.
Consequently, HaRav Gershon Edelstein said, that whoever studies Mussar and feels it is not worth the time, should know that it is not so but on the contrary, this is the preferred way in one's avodas Hashem. Surely, such study has an impact on his Torah learning, and his diligence in it, for it secures him a portion in Olam Haba through his study over the years, which is a high level indeed.
The truth is that it is against human nature to make a tremendous leap in one shot. One must proceed carefully [and toil] until he acquires perfection. Thus, the study of Mussar is the only method for self fortification and elevation. One cannot attain heights without Mussar, step by step.
The study of Mussar presents great difficulty since one does not feel its impact. But we should know that it does have its effect, though one cannot always feel it. When one studies Mussar over a long period, its seemingly weak impressions will combine to make a big difference and help him to attain true perfection.
It is natural that every spiritual influence on a person has a lasting effect, whether he feels it or not. Every study of Mussar similarly has an impact on a person, even though it is minimal and not apparent. But if one studies Mussar every day over a long period, he will surely feel its cumulative influence.
