What must have gone on in the first human mind to see a photograph? The past, always going, always gone—captured. Well, not exactly the past captured, but an image of a moment that otherwise would have faded from whatever mind(s) happened to be in that moment.

We’re so used to photographs and film we forget that for almost all history the past was “preserved” only in paint, or in words, or in doomed memory. And though each tick of the clock marks the making of more past, each instant of that past is lost to us, regardless of how easily we digitize it now.

The future is just as elusive, because the instant it comes it becomes the past. The future too, like the past, can haunt us; but at least with the future we can envision, anticipate, and perhaps create a hope that the past has locked out.

Eternity is more than just lots of time.

Then there’s the present, maybe nothing but the transition between future and past. It’s more mysterious than the past or future, because the moment it comes it’s gone; yet it never leaves.

“What, then, is time?” asked Augustine of Hippo. “The past is not, the future is not, the present—who can tell what it is, unless it be that which has no duration between two nonentities?”

Time is so close, so basic, that we can’t get behind it in order to understand it; hence, the concept itself remains as intangible as the three ways we divide it (past, present, future).

According to Einstein, space and time are a single entity (space time), and can’t exist without each other (try to envision time without space or space without time). In contrast, in the quantum realm, entities act as if time and space didn’t exist at all. Meanwhile, the faster one moves in a straight line at constant speed, the slower time moves. Or the stronger the gravitational field, the slower time moves too. (Time on the ground floor of the Burj Khalifa in Dubai moves more slowly than it does on the top one.)

Time is real, not just in our minds, because Genesis 1 shows it existed before we did. But it’s only with our minds, and all their limitations, that we experience time, which is why we struggle comprehending it.

And if time is hard to comprehend, what about eternity? Eternity is more than just lots of time. Every ratio is a division of sorts (1:3, 2:7, etc.). But how do you divide finite time by eternity? It would be like, perhaps, trying to divide a finite number by infinity. (Does that even work?)

We were created to exist, not in time, but in eternity. Thus, when promised, “Now this is eternal life: that they know you, the only true God, and Jesus Christ, whom you have sent” (John 17:3; see also Matt. 19:29; Mark 10:30; John 6:54; Rom. 5:21; 1 Tim. 6:19; 1 John 2:25),we’re being offered what we were to have had from the start.

Whatever the mysteries of time, how important that we do what’s right in each moment now, because in an instant each moment is gone; and when taken together, those moments will determine where we spend the eternity that follows.