See Poole on "Revelation 4:1", and following verses to Revelation 4:11. All the heavenly choir praise God upon this account, desiring that the Lord would fulfil what he had begun.
Related Commentaries of Revelation 19:4
Revelation 19:4
4 And the four and twenty elders and the four beasts fell down and worshipped God that sat on the throne, saying, Amen; Alleluia.