Psalm 138 - This psalm may have been written as a result of the opposition of the kings in 2 Samuel 5 and 8:1-14. David had recently become king of both the northern and southern portions of Israel. The Jebusites, Philistines, and Moabites did not wanted a strong and united Israel, but David trusted God and wanted the pagan nations and their kings to know that Israel's God was the God above all gods.
Psalm 139 - David highlighted and acknowledged God's omniscience (all-knowing), omnipresence (everywhere present), and omnipotence (all-powerful) in this amazing psalm.
For poetry experts, this psalm has four strophes of six verses each. A strophe is "a rhythmic system composed of two or more lines repeated as a unit; especially: such a unit recurring in a series of strophic units" (Merriam-Webster's collegiate dictionary, 10th ed.). It is similar to a stanza in music.
I remember reading through Psalm 139 with a Thai graduate student who had no concept of God prior to studying the Bible with me. She was so touched with the thought that God's hand would guide her. It was her first glimpse of God. It was exciting to experience this with her.
For some, the thought that God would know everything about us is a scary proposition. What is it for you?
Talk to God about it.
Pray through these psalms making them personal for you.