In order to lay a good foundation for several different points about joy I must first undo a teaching that is just slightly off. Have you ever heard someone say "There is nothing you can do to please God" ? What they really mean is there is no way you can ever earn Heaven. You can never be good enough to be worthy of Heaven. This part is true. You are not good enough and hands down salvation and entrance into Heaven is only through the Cross. But the error is when a Christian, who is not relying on works but on the finished work of Jesus, is told there is nothing he can do to please God. This part not only is wrong but it robs believers of a joyful motivator that is needed for long term endurance.
You can't earn Heaven but the believer can please God. Hebrews 13:16
16 And do not neglect doing good and sharing, for with such sacrifices God is pleased.
This verse clearly states that we can please our Heavenly Father by showing kindness to one another. Our actions of doing good and sharing pleases God. It does not save us but it makes God glad.
Did you ever give a present to someone and you just knew that when they opened it they would be glad? How did you feel when they responded with excitement? Weren't you glad when they were pleased? Or did you ever hold a baby and do all sorts of things to make the baby smile? And when you got that smile didn't it make you smile too?
In the above examples it was essential for you to know that the individual was pleased in order for your joy to flow. Likewise one essential of your joy flowing in your relationship with God is knowing that He is pleased with your good actions. When we know that we have made God glad then it gives us a reason to rejoice too.
Scripture quotations taken from the "NASB" ( www.lockman.org )