Why Hashem Made a Spirit of Folly
Beyond the reasons given for creating madness, the Chida finds a deeper purpose: it makes real teshuvah possible.
The Sages say that David wondered why Hashem created madness, fleas and spiders, and learned that each one once saved him. The Chida suggests another reason, for teshuvah, which was created before the world itself. A person sins only when a spirit of folly enters him. This gives the repentant some defense, since a fool is exempt from the mitzvos. It also answers a deeper question. Words of confession alone cannot undo a deed. But when the spirit of folly entered the sinner and made him stumble, teshuvah drives it out and he gains true understanding. That is a real act, a change in the person himself. Confession then joins a deed, and it can accomplish what words alone cannot. For the Chida, even foolishness has a place in Hashem's world, because the road back begins where a person was most lost.
Source: Devash LeFi, Letter Bet:2
If something you did recently still weighs on you, do not stop at feeling bad. Name it to yourself honestly, say it aloud in a quiet moment, and then do one concrete thing that is the opposite: apologize, return what was taken, or finally begin the habit you skipped. The Chida teaches that teshuvah becomes real when something in you actually changes. Start small today, and remember that a moment of folly does not define the person you are now.