JUDGMENT of the soul according to its faith and deeds on earth, is an unquestioned teaching of the Gospel. It is also a self-evident demand of human nature and reasoning.
The Christian Church places this judgment at the very moment of the death of the individual for two reasons:
1) Any moral progress of the soul is excluded after its separation from the body; and
2) there is no hope of repentance or betterment after death.
The moral progress of the soul, either for better or for worse, ends at the very moment of the separation of the body and soul; at that very moment the definite destiny of the soul in the everlasting life is decided. (see Androutsos Dogmatics p. 409). It will be judged not according to its deeds one by one, but according to the entire total results of its deeds and thoughts. The Orthodox Church believes that at this moment the soul of the dead person begins to enjoy the consequences of its deeds and thoughts on earth - that is, to enjoy the life in Paradise or to undergo the life in Hell. There is no way of repentance, no way of escape, no reincarnation and no help from the outside world. Its place is decided forever by its Creator and judge.
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The Last Judgment is not an act of overthrowing, the judgment of the soul at the time of its separation from the body, but rather to effect a union with the transformed, risen body with which the soul will continue to live forever. After the separation, the soul is conscious and consequently, feels, understands, and in general exercises all the energies of the soul (Revelation 6:9-10, 7:15; 1 Peter 3: 19; Hebrews 12:23; Luke 16:27-28). The word "sleep", by which death is characterized, does not refer to the soul, but to the body. In Matthew 27:52, we read that many Saints who had fallen asleep, were raised. The Last Judgment will take place on the second coming of Jesus Christ, a strong belief of the Church recorded in THE CREED that "He (Jesus Christ) shall come again with glory to judge the quick and the dead". The time of the second coming of Jesus Christ is not known and, according to Revelation, cannot be conjectured by any means.
Death, The Threshold to Eternal Life — Greek Orthodox Archdiocese of America