Prayer “often takes the form of importunity, passionate pleading to God, even wrestling with God. Such an attitude presupposes that God’s ultimate will is unchanging, but the way in which he chooses to realize this will is dependent on the prayers of his children. He wants us as covenant partners, not as automatons or slaves. In this restricted sense prayer may be said to change the will of God. But more fundamentally it is sharing with God our needs and desires so that we might be more fully conformed to his ultimate will and purpose.” - D. G. Bloesch, "Prayer," in Evangelical Dictionary of Theology, 867.