5. The second earthly and human limitation is that of time. Confined by space and time, man casts his eyes upward toward a Being who shall be infinite and eternal. Whatever time begets, time swallows up again. Transitoriness is the fate of all things. Everything which enters existence must end at last. “Also heaven and earth perish and wax old like a garment. Only God remains forever the same, and His years have no end. He is from everlasting to everlasting, the first and the last.” So speak prophet and psalmist, voicing a universal thought(249); and our liturgical poet sings: “The Lord of all did reign supreme Ere yet this world was made and formed; When all was finished by His will, Then was His name as King proclaimed. “And should these forms no more exist, He still will rule in majesty; He was, He is, He shall remain, His glory never shall decrease.”(250) 6. But the idea of God’s eternity also presents certain difficulties to the thinking mind. As Creator and Author of the universe, God is the First Cause, without beginning or end, the Source of all existence; as Ruler and Master of the world, He maintains all things through all eternity; though heaven and earth “wax old like a garment,” He outlasts them all. Now, if He is to manifest these powers from everlasting to everlasting, He must ever remain the same. Consequently, we must add immutability as a corollary of eternity, if the latter is to mean anything. It is not enough to state that God is without beginning and without end; the essential part of the doctrine is His transcendence above the changes and conditions of time. We mortals cannot really entertain a conception of eternity; our nearest approach to it is an endless succession of periods of time, a ceaseless procession of ages and eons following each other. Endless time is not at all the same as timelessness. Therefore eternity signifies transcendence above all existence in time; its real meaning is _supermundaneity_.(251) 7. This seems the best way to avoid the difficulty which seemed almost insuperable to the medieval thinkers, how to reconcile a Creation at a certain time and a Creator for whom time does not exist. In the effort to solve the difficulty, they resorted to the Platonic and Aristotelian definition of time as the result of the motions of the heavenly bodies; thus they declared that time was created simultaneously with the world. This is impossible for the modern thinker, who has learned from Kant to regard time and space, not as external realities, but as human modes of apperception of objects. So the contrast between the transient character of the world and the eternity of God becomes all the greater with the increasing realization of the vast gap between the material world and the divine spirit.