Charles H. Spurgeon on Psalms 30:9

What profit is there in my blood, etc. The little gain that the Lord would have by denying his people in the mercies they request, may also be used as a plea in prayer. David begs his own life of God, using this plea, What profit is there in my blood? So did the captive church plead Ps 44:12; "Thou sellest thy people for nought, and dost not increase thy wealth by their price." So then, poor saints of God when they come and tell the Lord in their prayers that indeed he may condemn, or confound, or cut or cast them off; he may continue to frown upon them; he may deny such and such requests of theirs, for such and such just causes in them; but what will he gain thereby? He may gain many praises, etc., by hearing them, and helping them; but what good will it do him to see them oppressed by the enemies of their souls? or what delight would it be to him to see them sighing and sinking, and fainting under sad pressures, etc.? this is an allowed and a very successful kind of pleading. Thomas Cobbet.