He not only praises God for his deliverance, but also confesses his fault, so that God alone may have the glory, and man the shame, and so that God may be exalted and man cast down. A humble approach to God demands both elements.  Praise as well as confession. 

We tend to use one or the other when dealing with God.  The combination of both allows God to deal with us.

Begin your day with Him by doing both.  Michael