For I said in my haste, I am cut off from before thine eyes: nevertheless thou heardest the voice of my supplications when I cried unto thee.
The conclusion recapitulates David's experience, with a view to strengthen all the saints in faith and love.
For I said. Translate as not connected with Psalms 31:21, but as the conclusion of the whole psalm, 'I truly, for my part (so the Hebrew), had said.'
In my haste - in the agitated haste of despondency: so the Hebrew expresses (1 Samuel 23:26).
I am cut off ... - as one cut off from hope, and already in the grave, beyond the reach of God's delivering mercy.