Isaiah 49:26
24 Can spoils be taken from a warrior, or captives be rescued from a conqueror? 25 Indeed,” says the Lord,“ captives will be taken from a warrior; spoils will be rescued from a conqueror. I will oppose your adversary and I will rescue your children. 26 I will make your oppressors eat their own flesh; they will get drunk on their own blood, as if it were wine. Then all humankind will recognize that I am the Lord, your Deliverer, your Protector, the Powerful One of Jacob.”
Revelation 16:6
3 Next, the second angel poured out his bowl on the sea, and it turned into blood, like that of a corpse, and every living creature that was in the sea died. 4 Then the third angel poured out his bowl on the rivers and the springs of water, and they turned into blood. 5 Now I heard the angel of the waters saying:“You are just—the one who is and who was, the Holy One—because you have passed these judgments, 6 because they poured out the blood of your saints and prophets, so you have given them blood to drink. They got what they deserved!”
Notes and References
"... The chief exegetical problem here is to identify the αὐτοῖς, “to them.” Should they be identified with the unidentified third-person plural subject of ἐξέχεαν, “they poured out” (that is, the murderers), or with “the holy ones and prophets”? The phrase “to give someone blood to drink” can mean “to die” (Isaiah 49:26, “I will make your oppressors eat their own flesh, and they shall be drunk with their own blood as with wine”), in which case this phrase expresses the principle of lex talionis. But it more frequently means “to kill” (Revelation 17:6; Numbers 23:24; 2 Samuel 23:17; 1 Chronicles 11:19; Jeremiah 46:10; Ezekiel 39:17–19; Zechariah 9:15; 1 Enoch 7:5; Aeschylus' Choephori 577–78; Sophocles' Electra 1417–21; Sophocles' Oedipus at Colonus 622; Greek Magical Papyri IV.2594–95, 2656–57). According to Charles, the meaning of this clause (which he renders “drink each other’s blood”) is that God will cause internecine war between Rome and her allies, yet the Johannine editor, he claims, did not understand this but took the clause to mean that as Rome shed the blood of Christians, so it will be forced to drink actual blood. Such internecine conflict is clear in 1 Enoch 7:5, but that is not what is said here in verse 6. Despite the parallels adduced above, it seems inappropriate to construe this clause to mean that God allows the saints and prophets to die ..."
Aune, David Word Biblical Commentary: Revelation 6-16 (p. 1078) Zondervan, 2017