As of August 18th, my husband and I will have been married twenty-one years, and have known each other for a total of twenty-four. It’s easy to believe after all of that time that I know everything there is to know about him.

There’s something wonderful about that, the comfort and ease and shorthand that come with more than half of a life with a person. There’s also something that can be reductive about that. Given the nature of sharing life and space, especially, you can start to believe that your knowing of your spouse is wholly encompassed by the daily things—what you see, touch, experience first-hand.

For example:

He never closes kitchen drawers all the way. His hiking boots leave scuff marks on the floor. He is relentlessly cheerful, and often expresses that through whistling. He’s usually about seven minutes behind me when it comes to being ready to go somewhere or do something. Technology confounds him and he has a hard time phrasing his computer questions in a way that I understand well enough to answer.

These sound like complaints. I mean them as observations, and as an observation about my observations, the things that seem to be at the top of my list of the Things I Know.

Marriage, especially the longer it goes, is so much about dailyness. And the Things I Know are so often reduced to these quotidian facts.

To my regret, I’m less likely to ponder other true things about the dailyness of our marriage. For example, that every single morning of it, when I finally wake up (a couple of hours after him), he seems genuinely happy to see me. If I’m cranky, I’ll sometimes ask, “What are you smiling about?” to which he’ll answer, “You.”

Also, that I can count on his kindness and patience, daily. That because he’s never, as long as I’ve known him, said a mean thing to me, I’m pretty sure he won’t today, either. He’ll do anything he can for my happiness.

He’s a loyal friend, an empathic and compassionate man, funny, creatively talented, and a dedicated teacher. He’s a good son and son-in-law. When my stepfather was dying—at home, with hospice care—and I was hiding in the basement, so afraid of what was happening and unable to do what was hard, my husband was the one who helped my mother clean my stepfather and change his sheets.

These, too, are Things I Know.

But because time can be such a bastard and humans are so quickly adaptable, even these truths, against my best efforts and intentions, can begin to feel mundane.

I recently encountered something I didn’t know about my husband. I discovered he’s not quite as technology-challenged as I thought, and this summer, he’s been working on a blog.

I have noticed he’s been at the computer a lot, and I guess when we’ve been on our walks he’s mentioned something about it but my mind tends to wander and I don’t always hear or listen to everything he says.

We do this to our spouses, I think, the not listening, because of our Things I Know lists and what we think there may or may not be left to learn. We probably do this with our parents and our children, too, and maybe even with ourselves.

I finally paid enough attention to realize, Oh, he really has a blog. Remembering the times I’ve expressed to him consternation if he hasn’t read mine, I read it. And thought:

Wow. Who is this person? He’s so smart, and such a deep thinker, and even more passionate than I realized about his vocation as a teacher and learner.

I felt and feel a little thrill to discover this person. A little romantic buzz, actually. This is someone I’d like to get to know.

It isn’t easy, as the years accumulate, to see a person anew. To see a marriage anew, ourselves anew. We love or don’t love the Things We Know, and these things construct our beliefs about who we are as a couple and what the possibilities are for us and what the limitations are.

But what if there is far more that we don’t know? As intimate as marriage is, you can never get inside someone else’s skin, inside another’s soul. Though there is much knowing made possible by twenty-one years of a shared life, we are probably still as much mystery as known.

It’s sometimes simpler to hold onto the knowns like the unclosed kitchen drawers than to imagine all that I don’t know, or to admit that my sometimes inflexible belief in the Things I Know may have shut down some potential growth in our marriage.

Henri Nouwen wrote that “the intimacy of marriage itself is based on the common participation in a love greater than the love that two people can offer each other.”

Likewise, there is a knowing greater than the knowing we can offer each other. We are, each, perfectly known by our creator. How do we exercise “common participation” in this greater, perfect knowing? I’m not sure.

As we approach our anniversary, I’m thinking about the unrevealed and undiscovered, and the truth that even in a close, healthy marriage there is what Nouwen calls “a holy vacancy, a space that is for the first Love, God alone.”

God is doing things there, known and unknown, in my husband’s life and in mine. We don’t directly participate in all of these things, all of the little changes and growths and losses and gains each of us experience. We can witness, celebrate, and mourn with the other.

We can practice revising, and possibly scrapping, the Things I Know, favoring instead a sacred curiosity about the things I don’t.