It's absolutely useless to post a single verse like this. Look at the entire psalm. It talks about what happened when Jerusalem was destroyed.

(Psalms 79 NIV) A psalm of Asaph. O God, the nations have invaded your inheritance; they have defiled your holy temple, they have reduced Jerusalem to rubble. {2} They have given the dead bodies of your servants as food to the birds of the air, the flesh of your saints to the beasts of the earth. {3} They have poured out blood like water all around Jerusalem, and there is no one to bury the dead. {4} We are objects of reproach to our neighbors, of scorn and derision to those around us. {5} How long, O LORD? Will you be angry forever? How long will your jealousy burn like fire? {6} Pour out your wrath on the nations that do not acknowledge you, on the kingdoms that do not call on your name; {7} for they have devoured Jacob and destroyed his homeland. {8} Do not hold against us the sins of the fathers; may your mercy come quickly to meet us, for we are in desperate need. {9} Help us, O God our Savior, for the glory of your name; deliver us and forgive our sins for your name's sake. {10} Why should the nations say, "Where is their God?" Before our eyes, make known among the nations that you avenge the outpoured blood of your servants. {11} May the groans of the prisoners come before you; by the strength of your arm preserve those condemned to die. {12} Pay back into the laps of our neighbors seven times the reproach they have hurled at you, O Lord. {13} Then we your people, the sheep of your pasture, will praise you forever; from generation to generation we will recount your praise.