31:9-18 David's troubles made him a man of sorrows. Herein he was a type of Christ, who was acquainted with grief. David acknowledged that his afflictions were merited by his own sins, but Christ suffered for ours. David's friends durst not give him any assistance. Let us not think it strange if thus deserted, but make sure of a Friend in heaven who will not fail. God will be sure to order and dispose all for the best, to all those who commit their spirits also into his hand. The time of life is in God's hands, to lengthen or shorten, make bitter or sweet, according to the counsel of his will. The way of man is not in himself, nor in our friend's hands, nor in our enemies' hands, but in God's. In this faith and confidence he prays that the Lord would save him for his mercies's sake, and not for any merit of his own. He prophesies the silencing of those that reproach and speak evil of the people of God. There is a day coming, when the Lord will execute judgment upon them. In the mean time, we should engage ourselves by well-doing, if possible, to silence the ignorance of foolish men.

14-18. In his profession of trust he includes the terms of the prayer expressing it.