Psalm 51 is a model of genuine, heartfelt, and contrite repentance. 

Psalm 51 is a psalm of David, when Nathan the prophet went to him, after he had gone in to Bathsheba. 

In Psalm 50 we see God acting in His role as judge over His people.

Psalm 50 is a psalm of judgment in which God is judging his people for worshipping him with wrong heart motives.

Psalm 49 is a wisdom psalm—a psalm that teaches—and its focus is on the foolishness of trusting in wealth.

A key idea in Psalm 49 is that it is very unwise to place our trust in wealth.

Psalm 48 includes praise for the Lord in celebration of Jerusalem—the city of the Great King. 

A great theme of Psalm 47 is praise to God as the great King of all the earth.

Psalm 46 is a psalm of assurance that God is with His people even in the midst of national and world crisis.

Psalm 45 seems to be a Messianic wedding song. It contains verses that are quoted in the New Testament Book of Hebrews.