1 After this I looked, and, behold, a door was opened in heaven: and the first voice which I heard was as it were of a trumpet talking with me; which said, Come up hither, and I will show thee things which must be hereafter.
John saw a door (portal or gate) opened in the sky. As it was opened he heard a trumpet-like voice speaking to him. The voice commanded that he ascend through the door into the very presence of the Lord. This trumpet reminds us that there will be such a call to the true church when Christ comes to Rapture it (1 Corinthians 15:52; 1 Thessalonians 4:16).
John was to receive further instructions regarding the future events on earth, in the Church, and amongst the false religions. “After this” is probably a reference to all the events of the Church Age, and therefore the Rapture of the Church before the Great Tribulation. He was given revelation about last days events, such as: the Tribulation (Revelation 4-18), Christ’s Second Coming (Revelation 19), Christ’s Millennial Reign (Revelation 20), and the eternal state (Revelation 21-22).
2 And immediately I was in the spirit; and, behold, a throne was set in heaven, and one sat on the throne.
Instantly John is transported through the door into third Heaven itself, the abode of God (2 Corinthians 12:2). He stood before the throne of God, and saw someone seated upon it. John’s physical body remained on the Isle of Patmos while he received this vision. Once in Heaven, the first person he sees isn’t some dead relative welcoming him in, but the Sovereign God seated upon His Throne.
3 And he that sat was to look upon like a jasper and a sardine stone: and there was a rainbow round about the throne, in sight like unto an emerald.
The figure he saw had the appearance of glorious beauty that mere human language cannot describe. The gemstones seek to describe the unspeakable glory of God, as does the green-coloured throne itself. A Jasper stone was placed in Aaron’s breastplate (Exodus 28:20), and the walls of the New Jerusalem are built with it (Revelation 21:18-19). The sardine is a ruby-like gemstone. A green tinted rainbow surrounds the throne (see Ezekiel 1:28). This rainbow speaks of God’s mercy and His promise. The rainbow was first seen after the Flood of Noah’s day. The rainbow is only mentioned four times in Scripture, and each time it is connected with judgement on earth and the accompanying mercy. The sight that greeted John revealed the glory of God in a way he could, in part, understand. “Who coverest thyself with light as with a garment” (Psalm 104:2).
4 And round about the throne were four and twenty seats: and upon the seats I saw four and twenty elders sitting, clothed in white raiment; and they had on their heads crowns of gold.
Twenty-four elders surround the throne. They are real redeemed men and not a symbol of something else as some suggest. These men may refer to the twelve leaders of Israel and the twelve apostles of Christ. They are obviously exalted saints since they are clothed in white and wear golden crowns – both of which are symbolic of imputed righteousness and eternal life. These men probably represent all who truly have faith in Christ. Revelation 1:6 refers to believers as “kings and priests” or “a kingdom of priests”, which is in keeping with 1 Peter 2:9, which says that we are “a royal priesthood”. It is interesting to note that there were 24 courses of priests in the first temple in Jerusalem (1 Chronicles 24:1-18).
5 And out of the throne proceeded lightnings and thunderings and voices: and there were seven lamps of fire burning before the throne, which are the seven Spirits of God.
Various voices appeared to come from the throne. Are these the voices of the Trinity? Also flashes lightning and thunders proceeded from it. This speaks of the terrible judgements that were about to be unleashed upon the earth. The seven lamps are said to be the seven spirits of God. The seven spirits may represent the seven angelic messengers which God has placed over each of the seven church or, as some believe, a reference to the Holy Spirit in His perfection. It is of great significance that the New Testament lists seven distinct titles for the Holy Spirit:  The Spirit of Truth (John 16:13);  Spirit of Holiness (Romans 1:4);  Spirit of Faith (2 Corinthians 4:13);  Spirit of Wisdom (Ephesians 1:17);  Spirit of Power (2 Timothy 1:7);  Spirit of Grace (Hebrews 10:29); and  Spirit of Glory (1 Peter 4:14).
6 And before the throne there was a sea of glass like unto crystal: and in the midst of the throne, and round about the throne, were four beasts full of eyes before and behind.
The sea of glass is similar to what Moses saw when he came into the presence of God (Exodus 24:9-10). Around the throne there are four living creatures. These are angelic beings (cherubim, seraphim or some other class of angels). They were able to see in all directions without turning their heads, for they had eyes all around their heads. It is possible that these beings are the “watcher” mentioned in Daniel 4:13. The Cherubim may have been used as guards, for they kept man from reentering Eden after the Fall (Genesis 3:24), and they appear to be guardians of God’s holiness in Revelation 4:6. They are always associated with God’s presence, and indeed even Satan, before he revolted against God was “the anointed cherub that covereth” (Ezekiel 28:14-16).
7 And the first beast was like a lion, and the second beast like a calf, and the third beast had a face as a man, and the fourth beast was like a flying eagle.
The first living creature looks like a lion, mighty and powerful. The second like a calf, faithful and obedient. The third like a man, intelligent and rational. The fourth like an eagle in flight, swift and clear sighted. Some commentators suggests that these creatures represent the four evangelists, Matthew, Mark, Luke, John. This may not need interpretation, for they may literally be angelic beings around the throne. If we believe the throne to be literal, why not the living creatures? Remember, all of this is a revelation of the glory of God.
8 And the four beasts had each of them six wings about him; and they were full of eyes within: and they rest not day and night, saying, Holy, holy, holy, Lord God Almighty, which was, and is, and is to come.
The living creatures each had six wings. Ezekiel and Isaiah record something similar to this vision (Ezekiel 1; Isaiah 6:1-5). Eyes appeared to cover each of the creatures (or their wings). These living creatures continuously offer praise and worship to God. Their eternal song rejoices in the fact that God is everlasting and almighty. “Holy, Holy, Holy” here connects with Isaiah 6:3 and proclaims the absolute holiness of the Triune God. “Almighty” is used to describe God’s power and authority 56 times in the Bible. “Which was, and is, and is to come” means that He is eternal, from everlasting to everlasting (Deuteronomy 33:27; Psalm 90:2). He is the King eternal who alone is immortal (1 Timothy 1:17; 6:16).
9 And when those beasts give glory and honour and thanks to him that sat on the throne, who liveth for ever and ever,
They offer endless glory, honour and thanksgiving unto God. With such an insight to the surroundings that greeted John, it was important that he refocuses his attention on the One seated on the Throne, the Eternal God.
10 The four and twenty elders fall down before him that sat on the throne, and worship him that liveth for ever and ever, and cast their crowns before the throne, saying.
The twenty-four elders also bow before Him who sits on the throne. As a sign of their submission, they cast their golden crowns before Him. This acknowledges that their righteousness and salvation comes from the Lord God who inhabits Heaven. This should always be our response to the Living God (Psalm 95:6). One day we are going to stand before His Throne and have our lives examined (Romans 14:8-10). The elders cast their crowns before the Lord as a sign that all they received came from and are truly His. We do not worship God in exactly the same way as the elders yet, but we can worship Him by presenting our complete lives to Him (Romans 12:1).
11 Thou art worthy, O Lord, to receive glory and honour and power: for thou hast created all things, and for thy pleasure they are and were created.
They also have a song to sing. Their song is all about Him who sits on the throne. All honour, glory, and majesty belong to Him. He is the Creator, Sustainer and Lord of everything. He is the one who created all things both in Heaven and on earth (Isaiah 44:24). It is far better to believe what the twenty-four elders say than Charles Darwin! Because God is our Creator, we ought to worship and praise Him as such (Psalm 95:6-7). Why were we and all things created? This verse gives us the answer. It was His will and good pleasure to do so.