In the Greek, these saints begin their urgent complaint with the words “how long,” thus emphasizing their impatience. They have been killed on account of the word of God and the witness they have borne, something most unjust given Jesus’ kingship. But the Lord, it appears, is not taking vengeance on their murderers; that is contrary to the promises the Lord gave in passages like Deuteronomy 32:35–36, Deuteronomy 32:41–42. So these saints do what saints before them have done: they voice the “how long” question (see also Psalm 35:1–28; Psalm 79:1–13; Daniel 12:6).
10 They cried out with a loud voice, “O Sovereign Lord, holy and true, how long before you will judge and avenge our blood on those who dwell on the earth?”