Testing to failure
I was trained as a chemical engineer and early in my career I actually did engineering work. One of my first assignments was to operate a pilot plant filled with an explosive gas at high temperatures and pressures. If anything failed, everyone in town would know it!
So it was important that all the tanks were pressure tested before they were installed. Some tanks were tested to failure. Every tank was tested at high pressure so it could be used at some lower pressure.
Here's the thing: when tanks are pressure tested, they're tested with water, not a gas. When a tank full of water fails, some water rushes out. When a tank full of gas fails, shrapnel flies everywhere. Safety first.
At our church we use three indicators of spiritual maturity: stability, gratitude, and generosity. So how do we discover our limits—or whether we've grown? We have to be pressure tested. Of course, real life pressure tests us every day—sometimes to the point of failure. But real life conditions aren't the safest. Failure can be explosive and damaging.
A better way to know ourselves is to engage in Gospel-centered community—with safe people—that will test our maturity. Everyone in the group should anticipate failures. And everyone in the group should be quick to extend grace.