CSL: being religious

The word religion is extremely rare in the NT or the writings of mystics. The reason is simple. Those attitudes and practices to which we give the collective name of religion are themselves concerned with religion hardly at all. To be religious is to have one's attention fixed on God and on one's neighbour in relation to God. Therefore, almost by definition, a religious man, or a man when he is being religious, is not thinking about religion; he hasn't time. Religion is what we (or he at a later moment) call his activity from outside.

CS lewis, "Lilies that Fester", in Christian Reunion and other Essays, p23.