No creature can be a child of God but because the goodness of God is in it; nor can it have any union or communion with the goodness of the Diety till its life is a Spirit of Love. This is the one only band of union betwixt God and the creature . . . Here the necessity is absolute: nothing will do instead of this will; all contrivances of holiness, all forms of religious piety signify nothing without this will to all goodness. For as the will to all goodnes is the whole nature of God, so it must be the whole nature of every service or religion that can be acceptable to Him.
William Law: The Spirit of Love.