To pray is to enter the house of God. The context for this worship, nonetheless, is still the life of struggle against evil. When the Christian rises, it is always on the battlefield.--Fr. Patrick Reardon, Christ in the Psalms, Psalm 5
For in their mouth there is no truth; their heart is vain. Their throat is an open sepulchre, with their tongues have they spoken deceitfully; judge them, O God.--Psalm 5:8-9
Sin is abhorrent to God. He not only loves justice; he also hates iniquity...When the psalmist prays for the destruction of the wicked, this is not personal sentiment, so to speak. it is a plea that God vindicate His own moral order. He hates it [sin] vehemently. Jesus on the Cross had not one word to say to the blasphemous, unrepentant thief...
The idea is abroad these days that , whereas the Old Testament God was a no-nonsense Divinity, the God of the New Testament is quite a bit more tolerant.
Such an idea would have surprised the Apostles. Romans 3:8-10, for instance, which is a melange of various psalm verses describing the evil of sin, cites a rather violent line from our present psalm with reference to evildoers: "Their throat is an open sepulcher." Indeed, the descriptions of sin in Romans 1 and 3 make a good commentary on many verses of Psalm 5.--Fr. Patrick Reardon, Christ in the Psalms, Psalm 5