She wrote upside-down on the stationery, and she apologized for the mistake.

But in truth, her upside-down words were the most right-side-up words I had read in a long time.

Her name was Paula. She wrote me the letter more than a decade ago, and it covered two sides of her notecard. I found it while cleaning our filing cabinets the other day.

When I held it in my hands, one long rubber-band of memory snapped me back to the day I got her letter.

Two days before the letter arrived in the mailbox, Paula had visited my home. She and I sat together on the couch, with crushed Cheerios underfoot. I had drawn on lipstick before she came over, but Cover Girl couldn’t cover the dark circles under my eyes. Nor could I hide the postpartum depression that had bulldozed my joy.

Paula asked to hold my crying baby.

It’s like she knew I was swimming through a soup of depression, while drowning under the hot guilt of my puny faith in God.

For some reason, my doubt felt like failure, like something that needed to be confessed. Like something I should feel terribly sorry for. So I kept my doubt walled off.

The wall crumbled the day Paula came by.

I didn’t intend to unzip my heart that day. Maybe all of my bone-tiredness had loosened my steely resolve to keep secrets. I can’t say for sure.

I do remember the softness of her eyes. The way she put her hands on my knees, like we were family. How she never swept away the crushed Cheerios with her feet. I remember mostly, how my doubt came up and out, like it was busting out of a prison.

A couple days afterward, her letter arrived.

“Don’t be discouraged by your doubting and empty feelings, Jennifer,” she wrote. “Even after all these years, I feel empty at times.”

I had no idea, until all these years later, how important that letter really was. And she would have had no idea how her small act of obedience—sitting down to write one letter—​would make a huge difference on the trajectory of one woman’s faith life.

Before Paula, I had feared condemnation for my doubt. But she held it gently in her hands.

These days, I hear a lot about how the church is failing people. How it’s too stodgy or irrelevant or happy-clappy or legalistic or pick-your-favorite-adjective-and-insert-it-here. No doubt, the church has been one or all of those things for many people down through the ages.

But for me on that day? Paula was church, the way church was intended to be, right in my living room, and again in my mailbox. Because she rang a doorbell. Because she picked up a pen.

It didn’t cost her more than the gas to our house, and the stamp on the envelope. And maybe a little time.

Mother Teresa once said the little things count for a lot:

“Not all of us can do great things, she said. “But we can do small things with great love.”

Small is the new big, which is good news for any of us who think that our small acts of obedience don’t amount to much.

Like Mother Teresa, Paula reminds us of this truth: it really is the little things.

 You want to make a difference today? Go ahead, think small.

Send your kid’s teacher a note of thanks. Bake cookies for your church janitor. Listen to the dreams of the woman who lives at the end of the cul de sac. Stop your car at the curb, and help your elderly neighbor pick up sticks. Send the note, and don’t fret if you write it on the card upside-down. Make the call. Pray your prayers. It matters. It really matters. 

Look: You don’t have to preach in stadiums or go viral or be a bestseller to radically alter the course of another human being’s life.

Small acts of love make a huge difference.

After that meeting with Paula all those years ago, I found a way to pluck my bravery out from under my doubt. Later, I became a leader in my church. I led community Bible studies, began a blog about my faith walk, and most recently, wrote a book to encourage other Christians who are trying to figure things out.

You won’t find Paula’s name on the spine of any books, but she’s built right into the spine of my faith story.

More than a decade ago, she wrote these words to me–

“Obviously, you are searching and studying and God is preparing you through that for what He has in store for you. Hang on—it could be a roller coaster ride but with God in charge, you’ll love it.”

She added a postscript in the corner: “Sorry I wrote this upside down.”