The "Great Tribulation" is a theological expression used to designate what in Scriptures is called "the day of Jehovah" or "the wrath to come." That there is to be a period when God will pour out His judgments upon the world is attested by practically all of the prophets, by the Lord Himself and by the apostles. Different names are given to it--Jeremiah called it "the time of Jacob's trouble." This period of the pouring out of God's wrath is so very definitely foretold that it is impossible for one to arrive at the wrong conclusion relative to it. So as to understand it correctly, let us examine two outstanding passages in the Old Testament before we look at the information given by our Lord in the Olivet discourse.

We have a very full and detailed description of this terrible time when God pours out His wrath upon the nations in Isa. 24:1-20. Because of limited space it is impossible to go into a minute description of the prediction, so we will call attention only to its high points. The first verse states, "Behold, Jehovah maketh the earth empty, and maketh it waste, and turneth it upside down, and scattereth abroad the inhabitants thereof." This presents a vision of the world destroyed by some great cataclysm. The desolation is that foretold in Jer. 4:23-31.

According to vs. 2, all people will share alike at that time. Doubtless this will be because all will be living on the same moral plane, practically speaking. Following this revelation, in vss. 3,4 we see the prophet using different figures to reiterate the thought of vs. 1 relative to the complete destruction of civilization. In vs. 5, however, he gives the reason why the Lord blots out the present-day civilization--the moral pollution of the world, the transgression of all laws and the breaking of the everlasting covenant. The Lord God Almighty, being holy, must punish sin and vindicate His holiness. In many passages of Scripture we see that in the latter days the world becomes worse and worse and that iniquity and sin become the order of the day. According to vs. 6, the punishment the Lord brings upon the world will destroy the bulk of its population--in fact, we are told here that the inhabitants of the world are "burned, and few men left." From other predictions (vss. 7-13) we see vivid descriptions of the horrors that will exist and the sufferings and privations through which the people of the world are destined to pass during the Tribulation. Everything will be in an abnormal condition. Nature will seem out of joint and the sufferings will be intense.

"Every cloud has a silver lining." The silver lining to the clouds of the Tribulation Period will be the mighty, sweeping revival that will at that time encircle the globe. This great conquest of truth is set forth in vss. 14-16a. The beginnings of this movement toward God is seen by the prophet to be in the country west of Palestine. Immediately, it sweeps on into the Holy Land. From there it, like ever-widening waves, moves to the uttermost parts of the earth. Myriads of people will come to the Lord during that time of judgment notwithstanding the odds against them. When God's "judgments are in the earth, the inhabitants of the world learn righteousness" (Isa. 26:9).

In the latter part of 24:16 the prophet's heart is wrung by the terrible distress which comes upon the world. According to vss. 17,18, escape from one calamity is no guarantee of future preservation for the following judgment will usually sweep one into a Godless, Christless grave.

The last sentence of vs. 18, "For the windows on high are opened, and the foundations of the earth tremble," indicates that there will be great changes and convulsions in nature--in the heavens above and upon the earth. The description of the havoc and the devastation that will be wrought upon the earth, especially toward the end of the period is set forth in the following words: "The earth is utterly broken, the earth is rent asunder, the earth is shaken violently" (Isa. 24:19).

All nature will be out of joint and a lack of coordination will be manifest in the material, physical universe, for "The earth shall stagger like a drunken man, and shall sway to and fro like a hammock; and the transgression thereof shall be heavy upon it, and it shall fall, and not rise again" (vs. 20). Our planet that has been moving without variation in its orbit throughout the millenniums will cease to travel with the same precision and regularity; from its orbit it will swerve toward the sun in one instance and from it in another--as a drunken man staggers along the road. This throwing of the physical universe out of its equilibrium is again compared to the swinging to and fro of a hammock. All of these movements and irregularities in nature will bring about great distress upon men and destruction of the present order.

The closing scene of the Tribulation will be brought to an end by the personal appearance of the Messiah from Heaven. Then, by His mighty angels, "the spirits of the high ones on high" (the fallen angels) will be incarcerated in the pits of darkness. At the same time the kings of the earth will be cast into Sheol. All of them will await the time of punishment after "many days" (vss. 21,22).

When these hosts of rebels against God are banished from the world, the Messiah will inaugurate His reign of righteousness in Jerusalem. His kingdom then will extend throughout the world and He will reign from sea to sea and from the river unto the ends of the earth (vs. 23).

Another vivid picture of the Great Tribulation is set forth by the prophet Zephaniah in 1:14-18:

The great day of Jehovah is near, it is near and hasteth greatly, even the voice of the day of Jehovah; the mighty man crieth there bitterly. That day is a day of wrath, a day of trouble and distress, a day of wasteness and desolation, a day of darkness and gloominess, a day of clouds and thick darkness, a day of the trumpet and alarm, against the fortified cities, and against the high battlements. And I will bring distress upon men, that they shall walk like blind men, because they have sinned against Jehovah; and their blood shall be poured out as dust, and their flesh as dung. Neither their silver nor their gold shall be able to deliver them in the day of Jehovah's wrath; but the whole land shall be devoured by the fire of his jealousy: for he will make an end, yea, a terrible end, of all them that dwell in the land."

Note that this time of trouble is called "the great day of Jehovah." At that time the mighty men will cry out in bitter anguish. According to vs. 15 it will be a "day of wrath, a day of trouble and distress ... a day of darkness and gloominess, a day of clouds and thick darkness." Not only will there be disorders in the natural realm but also there will be added to them the horrors of war and devastation by the plagues of the times.

The reason assigned for such a period of trouble is that men have sinned against God. His holiness demands that they be punished for their sins. At that time men's wits and their ingenuity will not avail. They will reap what they have sown.

These two passages are only samples of the many that appear throughout the Old Testament, but they give an idea of the graphic manner in which the prophets foretold this coming Tribulation Period.