John 17:13
But now I come to You, and these things I speak in the world, that they may have My joy fulfilled in themselves.
If there is anything that ought to characterize the life of a Christian, it is joy! Jesus spoke many times to His disciples about His joy being complete and full in them. His disciples were filled with joy as they realized who they were: children of God and joint heirs with Christ (Rom. 8:16-17). They had been dead in their sins but were now made alive in Christ (Rom. 6:4). They had once been helpless victims of death, but now death had no hold over them (1 Cor. 15:55 – 58). With such a marvelous salvation experience with Christ, how could the disciples be any less than joyful?
Don’t deny yourself that which is your birthright as a child of God. Don’t be satisfied with a joyless life. There ought to be in every Christian a deep, settled fullness of the joy of Christ that no circumstance of life can dispel. This comes as you allow the Holy Spirit to express Himself in your life. One of the fruits of the Spirit is joy (Gal.5:22). This joy is unlike any happiness that is produced by the world. It fills you and permeates everything you do.
Jesus did not pray that you would merely be happy or even that you would escape grief. He prayed that you would have the same joy that the Father had given Him: a divine joy, a joy that comes from a deep and unwavering relationship with the Father. It is a joy that is grounded so firmly in a relationship with God that no change in circumstances could ever shake it. This is the kind of joy that Christ is praying will be in you.
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Blackaby, Henry T. and Blackaby, Richard. Experiencing God day-by-day. Makati City: Christ Strengthening Ministry, 1998.