In ordinary parlance the words of the title refer to the exciting possibilities of physical science. Here they refer to the even more revolutionary impact of Christian Science in its encounter with the contemporary world.
Where are the frontiers? They're all around us and within us. They're where a material sense of things yields to spiritual sense—wherever the revelation of spiritual reality illumines the domain of material appearances and changes it. The discoveries to be found on these frontiers make all things new. They are discoveries not of theory but of practice, proof, demonstration.
Paul stood at a frontier of knowledge when, at Mars' Hill, he cited a local altar's inscription "TO THE UNKNOWN GOD" and told the highly literate Athenians, "Whom therefore ye ignorantly worship, him declare I unto you." To those who glorified the goddess Athena in marble statues and temples, his description of the one true living God, who "dwelleth not in temples made with hands," and in whom "we live, and move, and have our being," Acts 17:23, 24, 28. certainly must have been startling.
