Psalm 139
Eripe me, Domine.
A prayer to be delivered from the wicked.
Unto the end, a psalm of David.
Deliver me, O Lord, from the evil man: rescue me from the unjust man.
Who have devised iniquities in their hearts: all the day long they designed battles.
They have sharpened their tongues like a serpent: the venom of asps is under their lips.
Keep me, O Lord, from the hand of the wicked: and from unjust men deliver me. Who have proposed to supplant my steps:
The proud have hidden a net for me. And they have stretched out cords for a snare: they have laid for me a stumbling block by the wayside.
I said to the Lord: Thou art my God: hear, O Lord, the voice of my supplication.
O Lord, Lord, the strength of my salvation: thou hast overshadowed my head in the day of battle.
Give me not up, O Lord, from my desire to the wicked: they have plotted against me; do not thou forsake me, lest they should triumph.
The head of them compassing me about: the labour of their lips shall overwhelm them.
Burning coals shall fall upon them; thou wilt cast them down into the fire: in miseries they shall not be able to stand.
A man full of tongue shall not be established in the earth: evil shall catch the unjust man unto destruction.
I know that the Lord will do justice to the needy, and will revenge the poor.
But as for the just, they shall give glory to thy name: and the upright shall dwell with thy countenance.
..but you're quoting Psalm 140.