“The mystics keep telling us that the goal of prayer and the goal of our hidden life which should itself become more and more of a prayer is union with God. We use that phrase often, much too often, to preserve the wholesome sense of its awe-fullness. For what does union with God mean? It is not a nice feeling we get in devout moments. That may or may not be a bi-product of union – probably not. It can never be its substance. Union with God means every bit of our human nature transfigured in Christ, woven up into His creative life and activity, absorbed into His redeeming purpose, heart, soul, mind and strength. Each time it happens it means that one of God’s creatures has achieved its destiny.
And if men and women want to know what this means in terms of human nature, what it costs and what it becomes, there is only one way – contemplation of the life of Jesus Christ. Then we see that we grow in wisdom and stature not just for our own sakes – just to become spiritual – but that His teaching, healing, life-giving power may possess us and work through us; that we may lose our own lives and find His life, be conformed to the pattern shown in Him, conformed to the cross. Those are the rich and costly demands and experiences that lie before us as we stand and look at the Christ-child setting up a standard for both simple and learned, teaching the secrets of life; and what they ask from us on our side and from our prayer is a very great simplicity, self-oblivion, dependence and suppleness, a willingness and readiness to respond to life where it finds us and wait, to grow and change, not according to our preconceived notions and ideas of pace, but according to the overruling will and pace of God. Evelyn Underhill, Light of Christ, pg. 45-46