As John watched the events after the opening of the first ...seal by the Lamb, he saw a white horse with a rider holding a bow, wearing a victor's crown, and going forth to conquer. Because Christ in His second coming is pictured (Rev. 19:11) as riding on a white horse, some have taken it that this rider in 6:2 also must refer to Christ, as the white horse is a symbol of victory. Roman generals after a victory in battle would ride a white horse in triumph with their captives following. The chronology, however, is wrong, as Christ returns to the earth as a conqueror not at the beginning of the Tribulation but at the end of the Tribulation. Also the riders on the other horses obviously relate to destruction and judgment which precede the second coming of Christ by some period of time. A better interpretation is that the conqueror mentioned here is the future world ruler, sometimes referred to as Antichrist though Revelation does not use this term. He is probably the same person as the ruler of the people mentioned in Daniel 9:26. This ruler has a bow without an arrow, indicating that the world government which he establishes is accomplished without warfare. The future world government begins with a time of peace but is soon followed by destruction (1 Thess. 5:3). (Bible Knowledge Commentary, pg. 947)

With the breaking of the second seal a red horse appeared with a rider empowered to take peace from the earth (cf. "the red dragon," Rev. 12:3; the "scarlet beast," Rev. 17:3). In contrast with the first rider who has a bow without an arrow this second rider carried a large sword. This again was a picture of political power with the rider as the world ruler. (Bible Knowledge Commentary, pgs. 947-947)

With the opening of the third seal a black horse was revealed with a rider carrying a pair of scales in his hand. At the same time a voice was heard from among the four living creaures saying, "A quart of wheat for a day's wages, and three quarts of barley for a day's wages, and do not damage the oil and the wine!" A day's wages refers to a silver coin, the Roman denarius, worth about 15 cents, which was the normal wage for a worker for an entire day. So this passage is saying that in that food shortage an entire day's work would be required to buy either a quart of wheat or three quarts of barley. If one bought wheat, it would be enough for one good meal; if he bought barley, it would be enough for three good meals but nothing would be left for buying oil or wine. Famine is the inevitable aftermath of war. This will be a major cause of death in the Great Tribulation. The black color of the horse speaks of famine and death. (Bible Knowledge Commentary, pg. 948 )

A pale horse was introduced when the fourth seal was opened. "Pale" is literally a pale green (cf. the same word used of vegetation in Mark 6:39; Rev. 8:7; 9:4). John stated that the rider's name was Death and that hades was following close behind him. Here is the aftermath of war, famine, and death. With war and famine people fall prey to a plague and the wild beasts of the earth. The startling fact is revealed that a fourth of the earth, or approximately a billion people by today's population figures, will be killed by these means. It should be obvious that this is not a trivial judgment but a major factor in the Great Tribulation has begun. The first four seals may be considered as a unit and a general description of the Great Tribulation as an unprecedented time of trouble (cf. Jer. 30:7; Dan. 12:1; Matt. 24:21-22). (Bible Knowledge Commentary, pg. 948 )

With the opening of the fifth seal John had another revelation of heaven itself and his attention was directed to souls pictured as under the altar and identified as those who had been slain because of the Word of God and the testimony that had maintained. These are obviously martyrs, mentioned more in detail in Revelation 7. This makes it clear that souls will be saved in the Great Tribulation, but many of them will be martyred. [These martyrs] will cry out to the Lord, asking how long it will be before He will avenge them. In reply each is given a white robe and informed that the Tribulation is not over and that others must be martyred before God's judgment on the wicked and deliverance of the righteous occurs at the Second Coming. This passage shows that the time period is the Great Tribulation, but not its end. Spirits without any substance could not wear robes. The fact that they will be given robes supports the concept that when believers die they are given temporary bodies in heaven which are later replaced by resurrection bodies at the time of resurrection (cf. Rev. 20:4) (Bible Knowledge Commentary, pg. 948 )

As the sixth seal opened, John recorded that a great earthquake occurred. More dramatic than the earthquake was the transformation of the heavens with the sun turning black, the moon turning blood red, and stars falling like late figs from a fig tree. The heavens appared like a scroll being rolled up. At the same time, due to the earthquake, all the mountains and islands were moved from their places. Here again in the sequence of events, the end had not been reached as there was still another seal. But this was the most dramatic judgment thus far in this time of great distress before the Second Coming. ...The practical effect of the judgment was fear in unbelievers from all walks of life. They called on the mountains and the rocks to fall on them and to hide them from God's wrath. Their fear was so great they would rather be killed by a falling mountain than to face the wrath of the Lamb and Their wrath, referring to the anger of the Triune God. Again this is not a picture of ordinary trouble but the period of greatest distress in world history. (Bible Knowledge Commentary, pgs. 948-949 )

The opening of the seventh seal is a most important event, confirmed by the fact that there was silence in heaven for about half an hour after it was opened. The contents of the seven trumpets indicate that they differ from the seven seals. W. Graham Scroggie states, "The trumpets, therefore, do not double back over all or some of the seals, but lie under the sixth seal, and proceed from it" (The Great Unveiling, p. 111). He also holds that the bowls of the wrath of God (chap. 16) "do not double back over the seal and trumpet judgments" (p. 112). C.A. Blanchard holds the same position: "The series of three sevens are really included in one series of seven, that is, the seven trumpets are included under the seventh seal and the seven bowls are included under the seventh trumpet, so that we have in fact a single series in three movements" (Light on the Last Days, pg. 58 ). The seventh seal accordingly is important because it actually includes all the events from 8:1-19:10). (Bible Knowledge Commentary, pg. 949 )