Adam Clarke on Revelation 5:13

Every creature - All parts of the creation, animate and inanimate, are represented here, by that figure of speech called prosopopaeia or personification, as giving praise to the Lord Jesus, because by him all things were created. We find the whole creation gives precisely the same praise, and in the same terms, to Jesus Christ, who is undoubtedly meant here by the Lamb just slain as they give to God who sits upon the throne. Now if Jesus Christ were not properly God this would be idolatry, as it would be giving to the creature what belongs to the Creator.