It's All for the Best

SimchaMinute by Rabbi Avigdor Miller 

It is a mitzvah for a person to think that Hashem is doing the right thing... This is what we have in mind when say in the daily Shemoneh Esrei, "We trust in You." This trust is a mitzvah of the Torah. We fulfill this mitzvah when we think that what Hashem does and will do is for our best, even though we don't always understand why the result is the right one. — Ohr Avigdor Hakdama