Revelation 5

I don't think there is another writing in scripture of our premortal existence that seems to bring forth great emotion and love for the Savior as we John - -

"...saw in the right hand of him that sat on the throne a book written within and on the backside, sealed with seven seals." (New Testament | Revelation 5:1)

There is no doubt that this book contained the plan of salvation for all of the spirit children of our Father in Heaven as -

"...a strong angel proclaiming with a loud voice, Who is worthy to open the book, and to loose the seals thereof?
3 And no man in heaven, nor in earth, neither under the earth, was able to open the book, neither to look thereon." (New Testament | Revelation 5:2 - 3)

And thus John -

"...wept much, because no man was found worthy to open and to read the book, neither to look thereon." (New Testament | Revelation 5:4)

Can you imagine the disappointment and hopelessness of God's offspring in seeing no opportunity to be involved in this plan. That is to grow and progress and receive a body as God possessed. And than one declared -

"...Weep not: behold, the Lion of the tribe of Juda, the Root of David, hath prevailed to open the book, and to loose the seven seals thereof."
(New Testament | Revelation 5:5)

Is is any wonder when the Lord asked Job where he was -

"When the morning stars sang together, and all the sons of God shouted for joy?" (Old Testament | Job 38:7)

That is what John saw also. For John beheld -

"...in the midst of the throne and of the four beasts, and in the midst of the elders, stood a Lamb as it had been slain, having seven (JST:Twelve) horns and seven (JST:Twelve)eyes, which are the seven(JST:Twelve)Spirits of God sent forth into all the earth.
7 And he came and took the book out of the right hand of him that sat upon the throne.
8 And when he had taken the book, the four beasts and four and twenty elders fell down before the Lamb, having every one of them harps, and golden vials full of odours, which are the prayers of saints.
9 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." (New Testament | Revelation 5:6 - 10)

Is there any wonder the spirit children of our Father in Heaven did shout with joy! I couldn't help but as I read "they sung a new song", think of Alma's inquiry if the people had -

"...felt to sing the song of redeeming love..." (Book of Mormon | Alma 5:26)

I believe this was the new song as the Savior was worthy to take the book and open the seals.