A recurrent question has always been: What is the key?
And the answer that is always given is: “The righteous shall live by his faith.”
Because faith is the key that ensures the joy of life.
And the joy of life is the same as the joy of existence itself.
No matter what one’s destiny, whether to be a sinner or a saint, rich or poor, happy or wretched, the one great and decisive factor is joy in the knowledge that God is present.
And the more sincere this conviction, the more intense and alive one feels, because everyone lives by his faith.
–Rabbi Adin Steinsaltz