And the four and twenty elders and the four beasts - See the notes on Revelation 4:4, Revelation 4:6-7. As representatives of the church, and as interested in its welfare, they are now introduced as rejoicing in its final triumph, and in the destruction of its last foe.
Fell down - Prostrated themselves - the usual posture of worship.
And worshipped God that sat on the throne - Revelation 4:2-3, Revelation 4:10. That is, they now adored him for what he had done in delivering the church from all its persecutions, and causing it to triumph in the world.
Saying, Amen - See the notes on Matthew 6:13. The word here is expressive of approbation of what God had done; or of their solemn assent to all that had occurred in the destruction of the great enemy of the church.
Alleluia - See the notes on Revelation 19:1. The repetition of this word so many times shows the intenseness of the joy of heaven in view of the final triumph of the church.

The four and twenty elders - The true Church of the Lord Jesus converted from among the Jews. See Revelation 4:10; Revelation 5:14.

And the four and twenty elders and the four beasts,.... Mentioned in Revelation 4:4 and who represent the churches of Christ and ministers of the Gospel in the several periods of time, these join in the chorus, and praise the Lord on the account of the destruction of Rome, and ruin of antichrist; so they are often heard of in this book, when any remarkable thing is done, or when there is any breaking forth of the kingdom and glory of Christ; see Revelation 5:8 these
fell down; on their faces before God, as in Revelation 4:10 in great reverence of him, and of his righteous judgments:
and worshipped God that sat on the throne; described in Revelation 4:2 this refers to the public worship of God in the churches, by the ministers and members of them:
saying, Amen; Alleluia; they said "Amen", and signified their assent to what the much people in heaven had said, Revelation 19:1 and joined in the same "hallelujah", or expressions of praise to God, for this great appearance of his in the downfall of Babylon. Both these words are used together in Psalm 106:48, see Revelation 5:14.

beasts--rather, "living creatures."
sat--Greek, "sitteth."

And the four and twenty elders, and the four living creatures felt down - The living creatures are nearer the throne than the elders. Accordingly they are mentioned before them, with the praise they render to God, Revelation 4:9-10; Revelation 5:8, Revelation 5:14; inasmuch as there the praise moves from the centre to the circumference. But here, when God's judgments are fulfilled, it moves back from the circumference to the centre. Here, therefore, the four and twenty elders are named before the living creatures.