From Evelyn Underhill's Worship, 1936:
The painted cave of those prehistoric worshippers of an unknown God who were "simple-minded enough to give of their best to the supra-sensible powers," the Pagan temple, the Christian cathedral, are all expressions of the same fundamental human need to incoporate, make visible, the spirit of worship; to lavish skill, labour, and wealth on this most apparently "useless" of all the activities of man. So, too, the ritual chant, with its accompaniment of ceremonial movement and manual acts, is found to exert a stablizing influence at every level of his religious life. And when this costly and explicit embodiment is lacking, or is rejected where once possessed, and the Godward life of the community is not given some sensible and institutional expression within the social complex, worship seldom develops its full richness and power. It remains thin, abstract, and notional: a tendency, an attitude, a general aspiration, moving alongside human life, rather than in it.
It is true that worship, when thus embodied, loses - or seems to lose - something of its purity; but only then can it take up and use man's various powers and capacities, turning the whole creature towards the Eternal, and thus entering the texture of his natural as well as his supernatural life. Certainly, it is here that we encounter the greatest of the dangers that accompany its long history; the danger that form will smother spirit, ritual action take the place of spontaneous prayer, the outward and visible sign obscure the inward grace. But the risk is one which man is bound to take. He is not "pure" spirit, and is not capable of "pure" spiritual acts. Even though in his worship he moves out towards absolutes, and in and through that worship absolutes are revealed to his soul, it is at his own peril that leaves the world of sense behind, in his approach to the God Who created and informs it. This humbling truth must govern all his responses to Reality.