Psalms 96:1 (KJV) O sing unto the LORD a new song: sing unto the LORD, all the earth.
We are to sing a new song to the LORD. It is He who brings forth the new song in us.
“Psalms 40:3 (KJV) And he hath put a new song in my mouth, even praise unto our God: many shall see it, and fear, and shall trust in the LORD.”
New songs are sung in heaven.
“Revelation 5:9-14 (KJV) And they sung a new song, saying, Thou art worthy to take the book, and to open the seals thereof: for thou wast slain, and hast redeemed us to God by thy blood out of every kindred, and tongue, and people, and nation; [10] And hast made us unto our God kings and priests: and we shall reign on the earth. [11] And I beheld, and I heard the voice of many angels round about the throne and the beasts and the elders: and the number of them was ten thousand times ten thousand, and thousands of thousands; [12] Saying with a loud voice, Worthy is the Lamb that was slain to receive power, and riches, and wisdom, and strength, and honour, and glory, and blessing. [13] And every creature which is in heaven, and on the earth, and under the earth, and such as are in the sea, and all that are in them, heard I saying, Blessing, and honour, and glory, and power, be unto him that sitteth upon the throne, and unto the Lamb for ever and ever. [14] And the four beasts said, Amen. And the four and twenty elders fell down and worshipped him that liveth for ever and ever.”

Therefore let us all be encouraged today and every day to sing to the LORD a new song that He put in our hearts. Let us praise Him and give glory to Him alone. Let us sing about His greatness and His mighty salvation. Let us sing from our heart when we are alone and when we gather together. Let us sing with understanding and in tongues the LORD has given us.
“Ephesians 5:19-20 (KJV) Speaking to yourselves in psalms and hymns and spiritual songs, singing and making melody in your heart to the Lord; [20] Giving thanks always for all things unto God and the Father in the name of our Lord Jesus Christ;”