And my soul shall be joyful in the Lord; It shall rejoice in His salvation. (Psalm 35:9)
Joy is not synonymous with happiness. Happiness is based on what happens to us, while joy is based on who we are. Joy is not determined by life's situations. Joy controls our attitudes with regard to life's situations. Happiness on the other hand is created by events and our satisfaction with those events. Joy is the fruit of contentment. Joy says I need nothing but the Lord's salvation. Happiness is not a bad thing; it is a dependent thing. Joy, on the other hand, is independent. Happiness is subject to emotion, while joy rules emotion. Joyful people are more than often happy people while happy people are not necessarily joyful. If your attitude is ruled by events, you will have times of happiness. If your attitude is ruled by joy, you will, without exception, rejoice in your salvation. "Happy are the people whose God is the Lord!" With Christ we can have both. Without Him there will be only temporary happiness.