Psa 3:2 Many are saying of me, "God will not deliver him." Selah

The Psalmist is teaching that God focuses on communication in understanding us.  So the way the Psalmist speaks to himself is put in the scripture for our learning. What is the Psalmist teaching us? He is saying in this world we will always have a reputation that is described by others. How does the Psalmist respond? He tells God. You will find that we have a conversation that the Psalmist carries on with God that describes the normal communication that we will face in this world. He is showing the kinds of characters that are common in all generations.
The self talk teaches us to be aware of all of the kinds of things that sinners talk about. But in telling God the Psalmist is teaching God is viewing all the communication so that in knowing that God knows it in the text that we are not looking at the world in the wrong way. We are telling God what God is telling us through the psalmist. We must learn the Psalmist self talk so we understand who we are.

Psa 10:6 He says to himself, "Nothing will shake me; I'll always be happy and never have trouble."
How does a wicked man speak to himself? God is telling us so that we understand the characters in our world. He is teaching us that unless God tells us then we will develop a miss understanding of the person. The Psalmist is telling God. Sometimes we tell God something but we do not understand God's view because we need to be taught by the Psalmist.