The Greek word used for “kill” here means to put “to death by violence,” and directly implies murder. (The First Four Seals, pg. 24).

Strong’s G4969: sphazo, “… to slay, slaughter, butcher … to put to death by violence … mortally wounded.”

Joseph Thayer, A Greek-English Lexicon of the New Testament, p. 609.

Now because the same symbolism of a horse and a rider is used with this seal as with the first seal, traditionally, it was believed that this seal is related to the first in both time and meaning  (The First Four Seals, pg, 24).

“In the fulfillment of these figures there would naturally be a relation of the first four symbols historically, with the possibility of some overlapping in the fulfillment. Remember then, the design of the book is that the first four symbols in each group are interrelated.”

Fred Miller, Revelation: A Panorama, Ch. 3, “The Opening of the Seven Seals.”

For the Scriptural interpretation of the colors and symbols of the first four seals, as traditionally understood by the church, there is no better source than Albert Barnes, who employs minute detail in his explanation of each symbol, in Notes on the New Testament … : Revelation, pp. 132-158.

The Pattern of Using the Same Symbol
Scriptural Interpretation of the Symbols
Establishing the Timeline of the First Seal
The Five Good Emperors of the First Seal
Second Seal Symbolism
The Reign of Commodus
One Hundred Years of Disorder
Emperor Sold at Public Auction
The Choenix
Economic Collapse
The Weakened Roman State and Military
The Pale Horse
Pestilence in Ancient Rome
Depopulation in the Empire
The Christians Blamed for Roman Troubles

The Christian persecution for which John was in exile, began in 95 AD and Domitian was assassinated in 96 AD. (The First Four Seals: 96-300 AD, pg. 23).

See Persecutions under Domitian, from the Introduction Endnotes.

This period of righteous rule and the Pax Romana (Peace of Rome) lasted from 96 AD to 180 AD. (The First Four Seaks: 96-300 AD, pp. 23-24).

“If a man were called to fix the period in the history of the world, during which the condition of the human race was most happy and prosperous, he would, without hesitation, name that which elapsed from the death of Domitian to the accession of Commodus. The vast extent of the Roman empire was governed by absolute power, under the guidance of virtue and wisdom. The armies were restrained by the firm but gentle hand of four successive emperors, whose characters and authority commanded involuntary respect. The forms of the civil administration were carefully preserved by Nerva, Trajan, Hadrian, and the Antonines, who delighted in the image of liberty, and were pleased with considering themselves as the accountable ministers of the laws. Such princes deserved the honor of restoring the republic, had the Romans of their days been capable of enjoying a rational freedom.”

Edward Gibbon, The History of the Decline and Fall of the Roman Empire, Vol. 1, Ch. 3, “The Constitution in the Age of the Antonines, Pt. II.”

The death of Domitian occurred in 96, and Commodus was the son and successor of Marcus Aurelius. Aurelius’ reign ended in 180 with his death, and Commodus’ begun immediately after. Gibbon curiously says the peace lasted through four successive emperors, and names the four as Nerva, Trajan, Hadrian, and the Antonines. The Antonines, however, were two: Antoninus Pius, and Marcus Aurelius, which brings the total of the good emperors, to five.

See also The Five Good Emperors, from The First Four Seals Endnotes.

The Scripture itself interprets the meaning of the symbols. (The First Four Seals, 96-300 AD, pg. 23.)

For the Scriptural interpretation of the colors and symbols of the first four seals, as traditionally understood by the church, there is no better source than Albert Barnes, who employs minute detail in his explanation of each symbol, in Notes on the New Testament … : Revelation, pp. 132-158.

“I have also spoken unto the prophets,
and I have multiplied visions;
and by the ministry of the prophets have I used similitudes.”

Hos 12:11 [Hos 12:10 in Christian Bibles], Jewish Publication Society Bible.

A similitude, according to Webster’s, is a

“counterpart, double; a visible likeness, image; an imaginative comparison, simile; correspondence in kind or quality, a point of comparison.”

A symbol, the term most modern Christian Bibles use in Hos 12:10, according to Webster’s, is

“something that stands for or suggests something else by reason of relationship, association, convention, or accidental resemblance; especially : a visible sign of something invisible.”

Similitude : synonyms, related words : likeness, resemblance, similarity, semblance.

Merriam-Webster Thesaurus.