Charles H. Spurgeon on Psalms 86:7

In the day of my trouble I will call upon thee: for thou wilt answer me. A pious resolve backed by a judicious reason. It is useless to cry to those who cannot or will not hear; once convince men that prayer has no effect upon God, and they will have no more of it. In these busy days and especially in troublous times, men cannot afford to waste time in entreaties which must be unavailing. Our experience confirms us in the belief that Jehovah the living God really does aid those who call upon him, and therefore we pray and mean to pray, not because we are so fascinated by prayer that for its own sake we would continue in it if it proved to be mere folly and superstition, as vain philosophers assert; but because we really, indeed, and of a truth, find it to be a practical and effectual means of obtaining help from God in the hour of need. There can be no reason for praying if there be no expectation of the Lord's answering. Who would make a conscience of pleading with the winds, or find a solace in supplicating the waves? The mercy seat is a mockery if there be no hearing nor answering. David, as the following verses show, believed the Lord to be a living and potent God, and indeed to be "God alone", and it was on that account that he resolved in every hour of trouble to call upon him.