Psalms 96:1-13 (HCSB) 1 Sing a new song to the Lord; sing to the Lord, all the earth. 2 Sing to the Lord, praise His name; proclaim His salvation from day to day. 3 Declare His glory among the nations, His wonderful works among all peoples. 4 For the Lord is great and is highly praised; He is feared above all gods. 5 For all the gods of the peoples are idols, but the Lord made the heavens. 6 Splendor and majesty are before Him; strength and beauty are in His sanctuary. 7 Ascribe to the Lord, you families of the peoples, ascribe to the Lord glory and strength. 8 Ascribe to the Lord the glory of His name; bring an offering and enter His courts. 9 Worship the Lord in the splendor of [His] holiness; tremble before Him, all the earth. 10 Say among the nations: “The Lord reigns. The world is firmly established; it cannot be shaken. He judges the peoples fairly.” 11 Let the heavens be glad and the earth rejoice; let the sea and all that fills it resound. 12 Let the fields and everything in them exult. Then all the trees of the forest will shout for joy 13 before the Lord, for He is coming— for He is coming to judge the earth. He will judge the world with righteousness and the peoples with His faithfulness.
Why does the psalmist instruct us to sing a new song? In the Old Testament, worshipers sang a new song whenever God intervened on behalf of His people to deliver them. For example, in Exodus 15 Israel sang a new song after God delivered them from Pharaoh and the Egyptian army at the Red Sea. Also, the writer of Psalm 40 sang a new song after God delivered him from "the pit of destruction."
I hope you can sing a "new song" because the Lord has delivered you through Christ from the domain of darkness into His marvelous light! Through His mercy and grace you have been delivered from the cruel masters of sin and death and blessed with eternal life. Therefore, each of us should heed daily the psalmist's exhortation in Psalm 96:2-3. "Sing to the Lord, bless His name; Proclaim good tidings of His salvation from day to day.  Tell of His glory among the nations, His wonderful deeds among all the peoples."
Do you see what God is after? He seeks our worship and the worship of the nations! Why you ask? Is God an egotist? No, God does not need our worship or us for that matter!
God seeks are worship because He alone is worthy! Psalm 96:4-6 says, "For great is the Lord and greatly to be praised; He is to be feared above all gods.  For all the gods of the peoples are idols, But the Lord made the heavens.  Splendor and majesty are before Him, Strength and beauty are in His sanctuary." These verses declare that the Lord (revealed through the written and living Word) is the one true God. Every other god is an idol!
The rest of Psalm 96 exhorts the peoples and nations to worship the LORD. The last verse declares that the LORD is coming to judge the earth. On what basis will He judge? Worship. You see, it is either worship or wrath! If you think this is too harsh or don't believe me, read Romans 1:18-32.
Will just any worship due? No you must worship God in spirit and truth. How do you do that? It begins with a personal relationship with Jesus Christ. Remember Jesus' words in John 14:6. "I am the way, and the truth, and the life; no one comes to the Father but through Me. Therefore, there will be no worshipers of Allah, Buddha or any other god in heaven.
Folks, this is why it's so important we take the gospel to the nations! We must offer them the opportunity to worship the one true God! Are you ready? Are you willing? Romans 10:14-15 say, “How then will they call on Him in whom they have not believed? How will they believe in Him whom they have not heard? And how will they hear without a preacher?  How will they preach unless they are sent? Just as it is written, "How beautiful are the feet of those who bring good news of good things!"”
Let's take the gospel to the nations so we can all sing a new song together! Rev. 5:9-14 says, “And they sang a new song, saying, "Worthy are You to take the book and to break its seals; for You were slain, and purchased for God with Your blood men from every tribe and tongue and people and nation.  "You have made them to be a kingdom and priests to our God; and they will reign upon the earth."  Then I looked, and I heard the voice of many angels around the throne and the living creatures and the elders; and the number of them was myriads of myriads, and thousands of thousands,  saying with a loud voice, "Worthy is the Lamb that was slain to receive power and riches and wisdom and might and honor and glory and blessing."  And every created thing which is in heaven and on the earth and under the earth and on the sea, and all things in them, I heard saying, "To Him who sits on the throne, and to the Lamb, be blessing and honor and glory and dominion forever and ever."  And the four living creatures kept saying, "Amen." And the elders fell down and worshiped.”