If, then, we desire a simple test of the quality of our spiritual life, a consideration of the tranquility, gentleness ans strength with which we deal with the circumstances of our outward life will serve us better than anything that is based on the loftiness of our religious notions, or fervour of our religious feelings. It is a test that can be applied anywhere and at any time. Tranquility, gentleness and strength, carrying us through the changes of weather, the ups and downs of the route, the varied surface of the road; the inequalities of family life, emotional and professional disappointments, the sudden intervention of bad fortune or bad health, the rising and falling of our religious temperature. This is the threefold imprint of the Spirit on the souls surrendered to his great action.

—Evelyn Underhill, The Spiritual Life