George Foster said this quote

Like other spiritual fruit, joy must be cultivated.

~ George Foster

Choose joy! Joy is a choice. Joy is a witness. Joy is a therapy. Joy is a habit. If Jesus, who drank so deeply of the world's sorrow, could be filled with so much fun and laughter, then so can I.

~ George Foster

How do we handle feelings? What significance should we attach to them? If we want to keep our feelings from deceiving and defeating us, we must make some tough choices in our lives. We must trust God to keep our feelings under His control. We must make a choice to rejoice, and we must do it constantly. Feelings go where our thoughts and choices take them. So we can have confidence that God will use our choice and release to us the feelings that we need.

~ George Foster

Feelings are involuntary reactions, so God does not say, Feel joy. He says, Rejoice! It's a choice.

~ George Foster