Once a priest was speaking with a young woman. He explained that basically there are two kinds of Christians: thermometer Christians and thermostat Christians.
“Thermometer Christians and thermostat Christians?” the young woman asked.
“Exactly,” said the priest.
“Sorry, I don’t understand,” she replied.
“To understand,” said the priest, “you need to know the difference between a thermometer and a thermostat. Do you know the difference?”
“I think so,” she said. “A thermometer measures the temperature,” she continued, “and a thermostat… I’m not quite sure.”
“A thermostat,” said the priest, “changes the temperature. For example, if your thermometer is in a room that is 70° and you move it to a room that is 65°, the thermometer will change to 65°. If you move it to a room that is 80°, it will change to 80°. A thermostat works in the opposite way. If your thermostat is set at 70° and the room is 80°, it will cool the room down. If the room is 65°, it will warm it up.”
“Got it,” said the young woman. “But Father,” she immediately asked, “how does this relate to Christians?”
“It is very simple,” the priest said. “There are Christians whose lives are not consistent with their faith. They change their actions according to circumstances, like the thermometer. If they are in a difficult situation, they become angry and mistreat others. If they are in a happy situation, they laugh and treat others well. Their behavior also changes according to how others treat them. For example, if someone loves them, they love that person; if someone hates them, they hate that person. These Christians are like thermometers: they change according to the environment in which they live.”
“On the other hand,” the priest continued “there are Christians who always behave according to the Gospel. If someone hates them, they do not respond with hatred, because the Gospel says, Love your enemies. No matter if they are in a good or bad situation, they remain calm, because the Gospel says, Do not worry… your Father knows (Lk 12:29–30) what you need. These Christians are like thermostats, because by behaving in this way they change the environment rather than changing according to the environment. They influence the behavior of others through their example and their words.”
If we have a worldly heart, we will try to adapt our actions and words to the world, like a thermometer adjusting to the temperature of a room. If we have a Christian heart, we will shape our actions and words according to the Gospel, and we will help transform the world according to the Gospel—like a thermostat that changes the temperature of a room.
