God having created the Universe, is also responsible for its well-being. He is, therefore, the judge of all His creatures who possess a moral nature.
He has revealed that this present Creation will pass away and be replaced by a New Heaven and New Earth. There is also in the eternal State to be a Lake of Fire, which was not part of the original creation. (Gen. 1:1, Is. 65:17, Mt. 24:35, Rev. 20:11-21:8.)
While God, as Judge, is constantly passing judgments upon His creatures, e.g., at the Flood or Nineveh, yet these judgments are temporary and may be revised or revoked, as justice or mercy dictate. There are, however, before the eternal state begins two inexorable judgments which must be universally passed:—
(a) The Judgment of whether a person is to exist eternally in the Kingdom of God or in the Lake of Fire.
(b) The Judgment of where in that vast Kingdom of the New Heaven and Earth each one whose name is in the Book of Life is to be placed; whether in Heaven or Earth, and in what position in either. These Judgments, once passed, are unalterable.
Originally Heaven was created for Angels and earth for men; but the passage of time and the intrusion of sin have brought about modifications in the original structure.
The number of those who dwelt in Heaven and shared in its government has been greatly depleted by the rebellion of Satan and his Angels. God has revealed that it is not His intention to create more Angels to take their places; but, instead, to choose from amongst men those who might become His Sons by adoption, and hold a place higher than that ever offered to Angels, so that Jesus Christ would not be ashamed to call them brethren. (Rev. 12:7-9, 21:7, Heb. 2:5-18.)