The classical conception of God — supremely actual, perfectly immutable, unaffected by creaturely events — seemed to guarantee divine greatness by placing God beyond all contingency and change. Whitehead finds this conception self-defeating. A God who is unaffected by the world cannot be related to it; a God who is perfectly immutable cannot be the living God of religious experience, who acts, responds, and is moved by the suffering of creation. Classical immutability is purchased at the cost of the very relatedness that makes God religiously significant.
The dipolar God has two aspects that are always together. The primordial nature is eternal: God's perfect envisagement of all possible values, the ground from which every creaturely aim is drawn. The consequent nature is temporal: God's living reception of each creaturely experience, the ongoing integration of the world's becoming into the divine life. Neither aspect is God without the other. The primordial nature without the consequent nature would be an abstraction; the consequent nature without the primordial would lack order and direction.
Because God's consequent nature receives all creaturely experience, God receives all creaturely suffering. This is not a defect in God but a mark of divine love — the willingness to be genuinely affected by what happens in the world, to share in the world's joy and grief rather than observing from a safe distance. For Whitehead, a God who cannot be affected is not maximally great but maximally indifferent. The God of religion in the making is the God who is with the world in its adventure and its anguish.
Religion in the Making develops the dipolar conception in its fourth lecture ("Religion and Metaphysics"). The full systematic treatment comes in Process and Reality, but the Lowell Lectures show the theological motivation behind the metaphysical machinery — Whitehead is trying to make philosophical sense of the religious intuition that God is genuinely present to and moved by the world.