New Revised Standard Version
Why should the nations say, “Where is their God?” Let the avenging of the outpoured blood of your servants be known among the nations before our eyes.

Contemporary English Version
Why should nations ask us, "Where is your God?" Let us and the other nations see you take revenge for your servants who died a violent death.

New American Bible
Why should the nations say, “Where is their God?” Before our eyes make known to the nations that you avenge the blood of your servants which has been poured out.

Douay-Rheims Bible
Lest they should say among the Gentiles: Where is their God? And let him be made known among the nations before our eyes, By the revenging the blood of thy servants, which hath been shed:

Lest they should say among the Gentiles: Where is their God? And let him be made known among the nations before our eyes, By the revenging the blood of thy servants, which hath been shed:

wherefore

Psalm 42:3,10 My tears have been my bread day and night, whilst it is said to me daily: Where is thy God? . . .

Psalm 115:2 For thy mercy, and for thy truth's sake: lest the Gentiles should say: Where is their God?

Joel 2:17 Between the porch and the altar the priests, the Lord's ministers, shall weep, and shall say: Spare, O Lord, spare thy people: and give not thy inheritance to reproach, that the heathens should rule over them. Why should they say among the nations: Where is their God?

Micah 7:10 And my enemy shall behold, and she shall be covered with shame, who saith to me: Where is the Lord thy God? my eyes shall look down upon her: now shall she be trodden under foot as the mire of the streets.

let him

Psalm 9:16 The Lord shall be known when he executeth judgments: the sinner hath been caught in the works of his own hands.

Psalm 58:11 And man shall say: If indeed there be fruit to the just: there is indeed a God that judgeth them on the earth.

Psalm 83:17,18 Let them be ashamed and troubled for ever and ever: and let them be confounded and perish. . . .

Exodus 6:7 And I will take you to myself for my people, I will be your God: and you shall know that I am the Lord your God, who brought you out from the work-prison of the Egyptians:

Exodus 7:5 And the Egyptians shall know that I am the Lord, who have stretched forth my hand upon Egypt, and have brought forth the children of Israel out of the midst of them.

Ezekiel 36:23 And I will sanctify my great name, which was profaned among the Gentiles, which you have profaned in the midst of them: that the Gentiles may know that I am the Lord, saith the Lord of hosts, when I shall be sanctified in you before their eyes.

Ezekiel 39:21,22 And I will set my glory among the nations: and all nations shall see my judgment that I have executed, and my hand that I have laid upon them. . . .

by the

Jeremiah 51:35 The wrong done to me, and my flesh be upon Babylon, saith the habitation of Sion: and my blood upon the inhabitants of Chaldea, saith Jerusalem.

Revelation 18:20 Rejoice over her, thou heaven and ye holy apostles and prophets. For God hath judged your judgment on her.

revenging.

Romans 12:19 Revenge not yourselves, my dearly beloved; but give place unto wrath, for it is written: Revenge is mine, I will repay, saith the Lord.