New Revised Standard Version
Then my enemies will retreat in the day when I call. This I know, that God is for me.

Contemporary English Version
When I pray, LORD God, my enemies will retreat, because I know for certain that you are with me.

New American Bible
My foes turn back when I call on you. This I know: God is on my side.

Douay-Rheims Bible
Then shall my enemies be turned back. In what day soever I shall call upon thee, behold I know thou art my God.

Then shall my enemies be turned back. In what day soever I shall call upon thee, behold I know thou art my God.

When

Psalm 118:11-13 Surrounding me they compassed me about: and in the name of the Lord I have been revenged on them. . . .

Exodus 17:9-11 And Moses said to Josue: Choose out men; and go out and fight against Amalec: tomorrow I will stand on the top of the hill, having the rod of God in my hand. . . .

Jeremiah 33:3 Cry to me and I will hear thee: and I will shew thee great things, and sure things which thou knowest not.

then

Psalm 18:38-42 I will break them, and they shall not be able to stand: they shall fall under my feet. . . .

Psalm 27:2 Whilst the wicked draw near against me, to eat my flesh. My enemies that trouble me, have themselves been weakened, and have fallen.

John 18:6 As soon therefore as he had said to them: I am he; they went backward and fell to the ground.

for

Psalm 46:7,11 The Lord of armies is with us: the God of Jacob is our protector. . . .

Isaiah 8:9,10 Gather yourselves together, O ye people, and be overcome, and give ear, all ye lands afar off: strengthen yourselves, and be overcome, gird yourselves, and be overcome. . . .

Romans 8:31 What shall we then say to these things? If God be for us, who is against us?