not exhaust the difference between them. The marks of the concept of eternity are three: it
excludes a beginning, an end, and the succession of moments. God is unbegotten (
ἀ
γεννητος
) and
incorruptible (
ἀ
φθαρτος
) but also immutable.51 Between eternity and time there is a distinction
not only in quantity and degree but also in quality and essence. Even though he thought he could
conceive of motion in a world without any beginning, Aristotle already commented that though
time is not synonymous with motion, it is most intimately connected with it, with “becoming,”
that is, with the transition from the potential to the actual. Augustine expressed this somewhat
differently by saying that time exists only where the present becomes past and the future becomes
present.
“What, then, is time? If no one asks me, I know; if I want to explain it to someone who asks me, I
do not know. I can state with confidence, however, that this much I do know: if nothing passed
away, there would be no past time; if there was nothing still on its way, there would be no future
time; and if nothing existed, there would be no present time.”52 Time is not a separate substance,
a real something, but a mode of existence. If there were no creatures, there would be no time.
“Time began with the creature” is a truer statement than that which says, “The creature began
with time.”53 On the other hand, time is also not merely a subjective form of observation either,
as Kant thought.54 Admittedly, there is an element of truth here, too, and Augustine reasoned
that for humans to measure and compute time, a thinking mind is required—a mind that retains
the past by recollection, exists in the present, and expects the future, and to that extent measures
the times within itself.55 But in saying this, Augustine did not imply that there would be no
measurable and divisible movement of things if there were no thinking mind that counted and
measured it. A distinction needs to be made, however, between extrinsic and intrinsic time. By
extrinsic time we mean the standard by which we measure motion. In a sense this is accidental
and arbitrary. We derive it from the motion of the heavenly bodies, which is constant and
universally known (Gen. 1:14ff.). Time in this sense will one day cease (Rev. 10:6; 21:23ff.). But
intrinsic time is something else. It is the mode of existence by virtue of which things have a past,
present, and future as so many parts which, whatever the standard employed, can be measured
and counted. Now whatever can be measured and counted is subject to measure and number and
thus limited, for there always remains a measure and a number greater than that which was
measured and numbered.
Accordingly, the essential nature of time is not that either with respect to the earlier or the later
it is finite or endless, but that it encompasses a succession of moments, that there is in it a period
that is past, a period that is present, and a period that comes later. But from this it follows that
time—intrinsic time—is the mode of existence that is characteristic of all created and finite
beings. One who says “time” says motion, change, measurability, computability, limitation,
finiteness, creature. Time is the duration of creaturely existence. “Time is the measure of motion
in a movable object.” Hence, there can be no time in God. From eternity to eternity he is who he
is. There is in him “no variation or shadow due to change” [James 1:17]. God is not a process of
becoming but an eternal being. He is without beginning and end, but also knows no earlier and
