Charles H. Spurgeon on Psalms 25:3

Yea, let none that wait on thee be ashamed. Suffering enlarges the heart by creating the power to sympathize. If we pray eagerly for ourselves, we shall not long be able to forget our fellow sufferers. None pity the poor like those who have been or are still poor, none have such tenderness for the sick as those who have been long in ill health themselves. We ought to be grateful for occasional griefs if they preserve us from chronic hardheartedness; for of all afflictions, an unkind heart is the worst, it is a plague to its possessor, and a torment to those around him. Prayer when it is of the Holy Ghost's teaching is never selfish; the believer does not sue for monopolies for himself, but would have all in like case to partake of divine mercy with him. The prayer may be viewed as a promise; our Heavenly Father will never let his trustful children find him untrue or unkind. He will ever be mindful of his covenant. Let them be ashamed which transgress without cause. David had given his enemies no provocation; their hatred was wanton. Sinners have no justifiable reason or valid excuse for transgressing; they benefit no one, not even themselves by their sins; the law against which they transgress is not harsh or unjust; God is not a tyrannical ruler, providence is not a bondage: men sin because they will sin, not because it is either profitable or reasonable to do so. Hence shame is their fitting reward. May they blush with penitential shame now, or else they will not be able to escape the everlasting contempt and the bitter shame which is the portion of fools in the world to come.