God commanded Israel to invite the nations to join in declaring his glory. Zion is to be the center of world-winning worship (Isaiah 2:2-4; 56:6-8.) "Let this be written for a future generation, that a people not yet created may praise the Lord...so the name of the Lord will be declared in Zion, and his praise in Jerusalem when the peoples and the kingdoms assemble to worship the Lord" (Psalm 102:18.)

Psalm 105 is a direct command to believers engage in evangelistic worship. The Psalmist challenges them to "make known among the nations what he has done" (v.1.) How? "Sing to him, sing praise to him; tell of his wonderful acts" (v.2) Thus believers are continually told to sing and praise God before the unbelieving nations. (See also Psalm 47:1; 100:1-5.) God is to be praised before all the nations, and as he is praised by his people, the nations are summoned and called to join in song.

Peter tells a Gentile church, "But you are a chosen people, a royal priesthood, a holy nation, a people
belonging to God, that you may declare the praises of him who called you out of darkness into his
marvelous light." (I Peter 2:9.) This shows us that the church is challenged to the same witness that Israel
was called to--evangelistic worship. A key difference: in the Old Testament, the center of world-winning
worship was Mt. Zion, but now, wherever we worship Jesus in spirit and in truth (John 4:21-26) we have
come to the heavenly Zion (Heb.12:18-24.) In other words, the risen Lord now sends his people out
singing his praises in mission, calling the nations to join both saints and angels in heavenly doxology.
Jesus himself stands in the midst of the redeemed and leads us in the singing of God's praises (Hebrews
2:12), even as God stands over his redeemed and sings over us in joy (Zeph. 2:17.)

Read the whole article: http://www.redeemer2.com/resources/papers/evangelisticworship.pdf