Peter Pett's Commentary on the Bible
Psalms 6 - Introduction
Heading ‘For the chief musician on stringed instruments, set to the Sheminith (‘the eighth', a musical notation?). A Psalm to/for David (i.e. a part of the Davidic collection, dedicated to and possibly written by David).'
The psalmist cries desperately to God in his need. Possibly because he is overburdened by his sin which he seems somehow unable to control, something which has been brought home to him by a prostrating illness. The mention of his ‘enemies' comes in only in a secondary fashion as they seek to make the most of his grief. It is not they who mainly concern him, but his sin. But finally he ends on a note of triumph, and he knows that his enemies will be ashamed.
Then, having begun by praying for restoration of his health, and for an end to the chastening that he feels is the cause of the illness, he goes on to call on YHWH to restore him, describing his grief and misery, and finally tells his mocking adversaries that YHWH has done so, to their chagrin,