Joy is not a feeling in us. Joy does not enter into us. We enter into joy: "Enter into the joy of your Lord" (Mt 25:21).
Original sin is the proclivity to say "my will be done" instead of "thy will be done."
Reason alone cannot give you a whole steak, but it sure helps with identifying bologna.
Love is the binding force on every level of existence.
There is one and only one possible road to joy: selfless love.
Don't be more serious than God. God invented dog farts.