​Why Should We Feel Joy?

We must be grateful as well for all the other events of our history as well as for the events of our individual lives, each person according to what happened to him. When a boy becomes bar mitzvah he should celebrate having lived to this point. We must always realize that when Hashem gives a person benefits, He expects that individual to react with an effusion of enthusiastic joy and gratitude. — Ohr Avigdor Shaar Avodas Elokim