In a 2009 lecture on Leviticus 22-23, Dennis Prager said: Why does the Torah say to afflict oneself on Yom Kippur?
I never look forward to fasting. Perhaps you can tell.
I’ve done it since I was 12 (except for two occasions when I was sick).
This is the only time the Torah says to afflict yourself. All the other holidays you are to enjoy yourself.
The Torah confined a common religious instinct to one day a year. It is common for religious people to think that self-punishment and aescetism are holy. The medieval world had Christians wearing hair shirts. In the Shiite world, they whip themselves till they bleed.
When I was in yeshiva, [I was told about] a very very pious rabbi who on Yom Kippur was so careful not to drink that he would not even swallow his own saliva. He would spit it out. I remember thinking the man was an idiot. The thought of a guy spitting all Yom Kippur, what’s so pious about that? I would leave shul.
The Torah is saying that one day a year, oppress your soul. That’s it. Otherwise, enjoy your life.
This is very common among religious people, the harder it is to be religious, the closer you get to God.