BBQ-flavored potato chips are my favorite kind of potato chip and I’ve been fasting from them for 17 years. Seventeen years and nine months, to be precise.

But tonight, I broke that fast. (I nearly ate half a bag.)

Stacey’s college roommate had parents who chose to fast for her as she was growing up. They each chose a favorite food from which to fast for each of their children until the child reached 21 years old as a way to entrust their children to God.

Fasting is a way to pray with your body—giving up a desired good of any kind makes us acutely aware of its absence, and then we can invite God into that gap we feel in our desire. It’s an ancient practice, and extending a small fast over a long period of time can be just as effective as a big fast over a short amount of time.

When Stacey heard her roommate describe how her parents fasted for her, it made a big impression. So when we were becoming parents, we decided to do the same thing. For Oscar, our oldest (who is nearly 18), I gave up BBQ-flavored potato chips. For Simon, I gave up Snickers candy bars. For Lucy, I gave up cream soda. Stacey has her own corresponding fast for each child.

It has been an effective way for us to pray for the children. Not a week goes by that I’m not reminded of what I gave up for at least one of them, and it’s a good practice of discipline to turn away from something. Every time that I do, I clear space in my heart for love for that child to grow bigger.

While we don’t flaunt our fasting, we don’t hide it—the kids know what we’ve given up for them. I think I see in them a small measure of pride that their parents would pray for them in a committed way like this. That’s good currency for a family to trade in.

So why did I break that fast tonight? Well, technically, I’ve always told myself that when the child’s birthday comes around, I would allow myself an indulgence. But usually, I forget. And today was not Oscar’s birthday.

We had sloppy joes for dinner tonight, which is a specialty of mine if we need a quick dinner. And, as everyone knows, when you’re eating a sandwich, you need something crunchy to go along with it. Them’s the rules. I don’t make ‘em.

We were out of potato chips, though, so I texted Oscar before he came home from cross-country practice to pick up a bag from the store. “What kind?” he asked. “You pick,” I said. “Since you’re making the stop, you get to choose.”

“I only have 13 dollars,” he replied, as though it would be dicey to cover the cost with what he had in his wallet. What kind of potato chips do you think we eat, I thought, then I remembered he’s a teenager: even though he looks like an adult, he’s really got the brain of a large child. “Perfect,” I replied. “I’ll pay you back at home.”

(They cost three dollars, btw.)

So, imagine my delight when, faced with an entire aisle of potato chips, Oscar chose to bring home BBQ-flavored chips. With Stacey and Lucy out for the evening, and Simon not caring for BBQ flavor, I’ll be darned if I was going to make Oscar sit at that table and eat his and my favorite potato chips alone.

There’s a deeper subtext here, too, though, if I’m honest. Oscar’s a senior. He’s taking his SATs and applying for college and scholarships. I’m acutely aware that this time next year, his bedroom will turn into a guest room as he settles in at a college somewhere. (It could be just down the road, but he’ll still not be here.)

So I find myself trying to grab the moments as they stream off, tugging them back, as if to tell them, “Not yet—just a little longer.” We’ll be a different family this time next year, and if it’s anything like the past 17 years and nine months, the time will go quickly.

So the only thing I can do is savor the time we have left.