Temperatures where we live in Colorado can change quickly—sometimes within a few minutes. So my husband, Dan, was curious about the temperature differences in and around our home. As a fan of gadgets, he was excited to unpack his latest “toy”—a thermometer showing temperature readings from four “zones” around our house. Joking that it was a “silly” gadget, I was surprised to find myself frequently checking the temperatures, too. The differences inside and out fascinated me.

Jesus used temperature to describe the “lukewarm” church in Laodicea, one of the richest of the seven cities cited in the book of Revelation. A…