Revelation 17:6 And I saw the woman drunken with the blood of the saints, and with the blood of the martyrs of Jesus: and when I saw her, I wondered with great admiration.

"the saints" and "the martyrs of Jesus"

By mentioning two terms, this apparently may be because these are simply synonyms of the same group, or also, possibly two different groups.

If the woman is just a metaphor of the catholic church, then they would be synonyms of the Christian believers that the catholic church put to death, like during the Inquisition.

But if the woman represents an evil that has been around since ancient Babylon, but later manifested in imperial Rome, then later in the catholic church, etc;

in that case the two terms may be two groups, the first being from old testament times, and the second clearly in new testament times.

Psalms 116:15 Precious in the sight of the LORD is the death of his saints.

That Psalm was written in the old testament, yet has a timeless application.

But then when Daniel was was given a prophetic vision and explanation, in particular something about the eventual antichrist: 

Daniel 7:21 I beheld, and the same horn made war with the saints, and prevailed against them;

  25 And he shall speak great words against the most High, and shall wear out the saints of the most High, and think to change times and laws: and they shall be given into his hand until a time and times and the dividing of time.

Clearly, the meaning of the word saints, towards the end of the Babylonian captivity, was not understood to mean new testament Christians, and even primarily Gentile Christians.

No, it would have brought to mind Jewish saints, at that time, and even during the next half millennia.

But close to 600 years later, John was given something similar, in Revelation, about the antichrist:

Revelation 13:7 And it was given unto him to make war with the saints, and to overcome them: and power was given him over all kindreds, and tongues, and nations.

At that time, and forward, "saints", would usually bring to mind new testament believers.

But if coupled with Daniel 7, it would seem to imply both Jewish and Gentile "saints".

Yet, a little later, during the vial judgments, this is said:

Revelation 16:4 And the third angel poured out his vial upon the rivers and fountains of waters; and they became blood.

  5 And I heard the angel of the waters say, Thou art righteous, O Lord, which art, and wast, and shalt be, because thou hast judged thus.

  6 For they have shed the blood of saints and prophets, and thou hast given them blood to drink; for they are worthy.

So, does, "saints and prophets", only have a new testament meaning, or can it also reach back to include an old testament meaning?

All this, to wonder about, "the woman drunken with the blood of the saints, and with the blood of the martyrs of Jesus".

Does this have only a new testament understanding?

Or can it also include an old testament understanding?

.