Psalm 5:11 But let all those that put their trust in thee rejoice: let them ever shout for joy, because thou defendest them; let them also that love thy name be joyful in thee.
All believers are commanded, urged, and motivated to rejoice in the Lord. The Lord is always present to hear and help no matter what the circumstances are. David reacts to the world around him, which is filled with Sin and danger, by being joyful in the Lord. The things that were going on around David’s life did not always bring joy. But by faith he always had reason to be joyful, for the Lord was always there to defend him, forgive him, and hear his prayers.
We can, with the indwelling and the help of the Spirit, rejoice in the Lord. “Rejoice in the Lord always; again I will say, rejoice [Philippians 4:4].” Then v, 7: “And the peace of God, which surpasses all understanding, will guard your hearts and your minds in Christ Jesus.” Since the Lord is always with us His joy and peace is always there, too. And nothing and no one can take it away, unless we ourselves surrender it by listening to the temptations of the evil one, that our life is miserable. So we affirm and declare that we have an abiding joy within. God loves us, Jesus forgives us, and the Spirit assures and comforts the hearts with the Gospel. Therefore, we are are enabled to “give thanks always and for everything to God the Father in the name of our Lord Jesus Christ [Ephesians 5:20].” Constant thanksgiving is a key to open the joy that abides deep in the heart through faith in Christ.