Read Revelation 4:1-8)
After the Lord Jesus had instructed the apostle to write to the churches “the things that are,” there was another vision. The apostle saw a throne set in heaven, an emblem of the universal dominion of Jehovah. He saw a glorious One upon the throne, not described by human features, so as to be represented by a likeness or image, but only by his surpassing brightness. These seem emblems of the excellence of the Divine nature, and of God’s awful justice. The rainbow is a fit emblem of that covenant of promise which God has made with Christ, as the Head of the church, and with all his people in him. The prevailing colour was a pleasant green, showing the reviving and refreshing nature of the new covenant. Four-and-twenty seats around the throne, were filled with four-and-twenty elders, representing, probably, the whole church of God. Their sitting denotes honour, rest, and satisfaction; their sitting about the throne signifies nearness to God, the sight and enjoyment they have of him. They were clothed in white raiment; the imputed righteousness of the saints and their holiness: they had on their heads crowns of gold, signifying the glory they have with him. Lightnings and voices came from the throne; the awful declarations God makes to his church, of his sovereign will and pleasure. Seven lamps of fire were burning before the throne; the gifts, graces, and operations of the Spirit of God in the churches of Christ, dispensed according to the will and pleasure of Him who sits upon the throne. In the gospel church, the laver for purification is the blood of the Lord Jesus Christ, which cleanses from all sin. In this all must be washed, to be admitted into the gracious presence of God on earth, and his glorious presence in heaven. The apostle saw four living creatures, between the throne and the circle of the elders, standing between God and the people. These seem to signify the true ministers of the gospel, because of their place between God and the people. This also is shown by the description given, denoting wisdom, courage, diligence, and discretion, and the affections by which they mount up toward heaven.
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Revelation 4 Bible Commentary – Matthew Henry (concise) (christianity.com)
2 Immediately I was in the Spirit. Behold, there was a throne set in heaven, and one sitting on the throne 3 that looked like a jasper stone and a sardius. There was a rainbow around the throne, like an emerald to look at