Revelation 6:8

"And when He had opened the fourth seal, I heard the fourth living creature saying, Come and see. And, lo, a pale horse; and he who sate upon him was named Death." For the pale horse and he who sate upon him bore the name of Death. These same things also the Lord had promised among the rest of the coming destructions-great pestilences and deaths; since, moreover, he says:-

"And hell followed him." That is, it was waiting for the devouring of many unrighteous souls. This is the pale horse.

There are two parts in the world, that which belongs to God and that of the devil. That which belongs to the devil is further divided into three parts, which are both within and outside [the church]. These are the Gentiles, false brothers and those separated by open error or schism. And these three parts are those that war against the one. This one is said to consist of three fourths, either because it believes in the threefold unity or because it is distinguished into orders by the goodly variation of three vocations, that of the virgins, of the widows and of the married. He says that now power is given in these three fourths. He speaks of the church which is one, and because the threefold vocation relates to one head, it consists from the three fourths in the stability of a square. As it says, “built upon the foundation of the apostles and the prophets, Christ Jesus himself being the chief cornerstone.” He foretells that the church will be placed into stress by the attacks of evil people, from the Gentiles, from false brothers and by heretical depravity. And this is also to be recognized in the number of the messengers, that the very same good would oppose three evil enemies—the red horse with the sword, the second, black horse with the balance, and the third, pale horse with the sign of death, for the sword signifies war, the black horse famine and the pale horse death. And since he mentions the plagues one by one, he foretells all the future outbreaks of plagues by enumerating them in or through the third, the names of the beasts being added. We may remain undecided whether the speech is literal or figurative. For a visible sword is commonly used against the body, while a spiritual sword is used against the soul. Similarly concerning famine, it can mean here either a famine of the Word of God or a famine that affects the body. And likewise concerning death, it can here mean either eternal death that affects souls or that temporal death that concerns bodies. Nonetheless, it is clear that the fourth good part, which is opposed by the three evils, is made to struggle in time by all of these visible persecutions. For those who are called according to the purpose of the will of God shall remain in the perfect number of the elect, especially those whom he wills to be preserved by the inviolate sacraments of the wine and oil. For when he said, “Do not harm the wine and oil,” he was indicating the price of redemption in the wine and the anointing of baptism in the oil. Indeed, the Lord clearly said in the Gospel, “Father, those whom you have given to me, I have guarded, and none of them is lost but the son of perdition.”

In the pale horse we perceive evil people who never cease to incite persecutions. And these three horses are one, who came out after the white horse and against it. And they have as their rider the devil, who is death. And so, the three horses are interpreted to be war, famine, and pestilence. For in the Gospel, the Lord foretold of these things, and they have already occurred, and as the day of judgment draws nearer will occur even more.

This sequence of events has happened before and reflects also contemporary occurrences. For as Eusebius says in the eighth chapter of the ninth book of his Ecclesiastical History, at the height of the persecution, when Maximinus was Roman emperor, both famine and pestilence along with other things fell upon them, so that such an innumerable multitude perished that they could not be buried. At that time indeed the Christians zealously undertook the task of burying the dead and by their love of humanity led those who had been deceived to the recognition of the truth. Moreover, the Armenians resisted the Romans, he says, so that many were killed with the sword and the bodies of the dead were eaten by dogs. Finally, those left alive began to kill the dogs, fearing that they themselves might die and that the living would become their tombs. For it was not impossible that even wild animals shared the same meal with dogs on account of the abundance of food. We know that even in our own times similar things have happened.

And behold, a pale horse, etc. Heretics who mask themselves as Catholics, worthy of the inhabiting death, drag after them a host of the lost. For the devil and his ministers are metaphorically called death and hell, as they are the cause of death and hell for many. It can also be simply understood that here the spiritually dead, there eternal punishment follows.

And power was given to him over a fourth of the earth. Behold, the madness of Arius, born in Alexandria, reached as far as the Gallic Ocean, not only persecuting the pious bestially with famine of the word of God but also with physical sword. Another version translates it as a fourth part, because the three evil horses, relying on the devil as their leader, ride against the fourth cavalry of the Church.

And when he had opened the fourth seal, I heard the voice of the fourth living creature, saying: Come, and see. And behold a pale horse, and he that sat upon him, his name was Death, and hell followed him. The people represented by the pale horse are the same as those represented by the red horse, their spiritual death being now symbolized by the pallor of the horse. It is right to say that death, that is the Devil intending to fight against the living, sits on them, because he seeks to extinguish the lives of the elect by the agency of those he has already killed spiritually. Hell means those in whom death dwells. Therefore hell follows death, because the wicked imitate the Devil. We may also understand by the pale horse the heretics specifically. And power was given to him over the four parts of the earth, to kill with sword, with famine, and with death, and with the beasts of the earth. There are two parts in this world, namely Christ's and the Devil's; but Christ's part is not divided, according to this: One is my dove; [Song 6:8] whereas the Devil's part is divided into four parts: pagans, Jews, heretics, and bad Catholics. Therefore there are as many plagues as there are parts of the Devil. It has already been explained how he kills with sword, with famine, and with death. As for the beasts, by them are represented ungoverned pulsions. So our enemy kills the souls of the reprobates with beasts because when fleshly pulsions are not restrained by the cages of the divine commandments, they are made wild, so to speak, by the impulse of diabolic incitement, and hurl the lives of the wretched down every precipice.

It is the breaking of the fourth seal and the beginning of the release from the sin of Adam's transgression. For this release is the indicator of reconciliation with God. For if "our sins separate us from God", as Isaiah says (Isa. 59:2), then their removal brings us back into fellowship. But what is the remedy? The wounds of Christ, through which we have been freed (see 1 Peter 2:24; Isa. 53:5). For since we were condemned by the pleasure of tasting, we have been healed by its opposites. Opposite to pleasure are the wounds, which bear the painful sensation, all of which Christ endured on our behalf, through which we were led to the corruption of death, but He endured it through opposites: through obedience, disobedience (see Rom. 5:19); through painful submission, pleasure; through the brave placing of His hands upon the cross, which had rashly touched the forbidden tree.

Of which it is said to have occurred, by the command of the fourth living creature saying, "Come." I looked, and behold, a pale horse; and the one sitting on it was named Death, and Hades followed with him. And they were given authority over a fourth of the earth. The pale horse is a symbol of wrath; for the bile is pale green, and so it is called by physicians.

Death and Hades were indeed sent forth spiritually to overthrow the deceitful demons and to exact justice for the destruction of humanity. However, since the saving work of Christ's passion had not yet been accomplished through the Revelation, by which He atoned all the sins committed against us, the complete destruction of the demons had not yet occurred; rather, only a quarter part had been destroyed.

This destruction is metaphorically called a slaughter and famine by those who long ago worshipped them; and death, the end of their tyranny, is brought about through death itself, and their annihilation by the beasts of the earth;

beasts of the earth being the passions of pride and vanity in the demons. Though these demons are earthly by nature, as they delight in the earthly passions that afflict those on earth, even though they have a spiritual nature, they are weakened and consumed as they are cast out from their dominion over humanity.