The four living creatures and the twenty-four elders fell down before the Lamb after He had taken the book. Angels and apostles refused to be worshipped (Rev. 22:8-9; Acts 14:12-18). Jesus allowed individuals to worship Him (Matt. 14:33; Matthew 4:10).
1. Each one had a harp: Harps were used in the temple service (1 Chron. 16:37; 2 Chron. 5:12-13)
2. ” ” ” golden bowls full of incense: which are the prayers of the saints
3. They sing a new song, “You are worthy to take the book, and to open its seals: for you were slain and did purchase     unto God with your blood men of every tribe, and tongue, and people, and nation. You made them be unto our     God a kingdom and priests, and they reign upon the earth.”
The song of Moses was sung when God delivered Israel from Egyptian bondage (Exodus 15:1-21). It celebrated God’s victory over Egypt and thanked Him for their deliverance. This new song was similar in that it was a song of thanksgiving for deliverance from bondage, but the rejoicing was release from sin and praise to the Lamb for His victory over Satan. The blood of the Lamb was offered once for all (Heb. 10:11-12; 1 John 2:2).  God’s desire was to have a people who would be a kingdom of priests.  Israel was rejected as Jehovah’s priestly kingdom, but the called-out new Israel make up His royal priesthood (cf. 1 Peter 2:5, 9-10). Thus, a new song is sung to celebrate a new kingdom and covenant relationship with God as priests.
These twenty-eight voices are joined by over a hundred million angels who sing, “Worthy is the Lamb that has been slain to receive the power, riches, wisdom, might, honor, glory, and blessing.” The worship and praise extend to every created thing on the earth, under the earth, and on the sea. This includes all saints and sinners, dead and alive. John hears them singing, “Unto him that sitteth on the throne, and unto the Lamb, be the blessing, the honor, the glory, and the dominion forever and ever.”
The four living creatures said, “Amen.” and the elders fell down and worshiped.