Charles H. Spurgeon on Psalms 57:2

I will cry. He is quite safe, but yet he prays, for faith is never dumb. We pray because we believe. We exercise by faith the spirit of adoption whereby we cry. He says not I do cry, or I have cried, but I will cry, and indeed, this resolution may stand with all of us until we pass through the gates of pearl; for while we are here below we shall still have need to cry. Unto God most high. —Prayers are for God only; the greatness and sublimity of his person and character suggest and encourage prayer; however high our enemies, our heavenly Friend is higher, for he is Most high, and he can readily send from the height of his power the succour which we need. Unto God that performeth all things for me. He has cogent reason for praying, for he sees God performing. The believer waits and God works. The Lord has undertaken for us, and he will not draw back, he will go through with his covenant engagements. Our translators have very properly inserted the words, "all things, "for there is a blank in the Hebrew, as if it were a carte blanche, and you might write therein that the Lord would finish anything and everything which he has begun. Whatsoever the Lord takes in hand he will accomplish; hence past mercies are guarantees for the future, and admirable reasons for continuing to cry unto him.