Revelation 16:5-7 "And I heard the angel of the waters say, Thou art righteous, O Lord…because Thou hast judged thus. For they have shed the blood of saints and prophets, and Thou hast given them blood to drink; for they are worthy. And I heard another out of the altar say, Even so, Lord God Almighty, true and righteous are Thy judgments"
"This is the only place in the Revelation where the altar is said to speak, though we have heard before of a voice from the horns of the altar (Rev. 9:13). In Revelation 8:5 we find the altar connected with the prayers of the saints, and as a result of their prayers fire is taken from off the altar and cast into the earth. The fire is a symbol of purging and purification, and the voice from the horns of the altar comes also as a result of the prayers of God’s elect and releases a mighty deliverance in the lives of God’s called and chosen remnant. Here in our text the altar is emphasizing that God’s judgments in the midst of His people are true and righteous, that is, they are just and purposeful. The message is just this — God is doing what He has to do in order to correct what is wrong in His people, and what He does is just and redemptive, bringing deliverance and restoration."
"Another strange statement is that because they have shed the blood of saints and prophets, God is giving them blood to drink: for they are worthy. That last phrase simply means "for they deserve it!" We don’t like to think of God giving people what they deserve, but in this case that is exactly what He is doing. Shed blood signifies death. That is what they deserve to drink, death to themselves. The reference is to the fact that the church systems have slain, both figuratively and literally, the righteous men and prophets sent to speak the words of God to them through the ages. Thousands have been the martyrs slain by the church systems in ages past and even in recent times! They chose to drink from the human sources of this old world. Thus they wickedly rejected the living streams of water flowing out from God’s chosen vessels! So now He is causing them to drink a full dose of the death they have chosen! Let them drink blood! Oh, yes! They deserve it! It is not vindictiveness — it is correction! The Spirit is revealing to them the awful depths of the death that flows in the streams of man! And it is for their good, for their deliverance, and ultimate perfection!"
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"The divine pattern in all these things becomes clear once we understand the great truth that there are revealed in the wonderful book of Revelation two heavens and two earths! The blessed Seer of Patmos beheld these in rapt vision and recorded what he saw in these inspired words, "And I saw a new heaven and a new earth: for the first heaven and the first earth were passed away; and there was no more sea" (Rev. 21:1). There is an old heaven and there is a new heaven! There is an old earth and there is a new earth! The old heaven and earth pass away, but we look for new heavens and a new earth wherein dwelleth righteousness (II Pet. 3:13). It should be clear to any thinking mind that the old heaven with its sun, moon, and stars, is not our natural solar system or the star-studded universe we behold in the night sky. That is not the old heaven John is writing about! Rather, it is the old order that men have lived under, the old world of human consciousness, worldly society, and man-made religion with all its luminaries — the "lights" or personalities and institutions that govern, control, dictate, constrain, inspire, and direct men’s thinking, understanding, ways, will, desires, ambitions, and conduct in the world of humanity."