6:4 David appealed for deliverance from his ailment first claiming God's loyal love to him. God had promised to bless David and had delivered him many times before. The king besought Him to prove faithful to His character and save him again.
6:5 The second reason David cited was this. If he died he could not give God public praise for delivering him, and God would therefore not receive honor among His people as He would if He spared David's life. Believers in David's time had some revelation of life after death (cf. Job 19:25). David's expression here does not deny that knowledge. He was saying God would lose praise among the living if David died. Sheol was the place where Old Testament saints believed the spirits of the dead went. This term often occurs in the Old Testament as a synonym for death and the grave.
