Read Romans 12:1-2
1 And so, dear brothers and sisters, I plead with you to give your bodies to God because of all he has done for you. Let them be a living and holy sacrifice—the kind he will find acceptable. This is truly the way to worship him. 2 Don’t copy the behaviour and customs of this world, but let God transform you into a new person by changing the way you think. Then you will learn to know God’s will for you, which is good and pleasing and perfect. (NLT)
Thermostats and thermometers are entirely different instruments even though they sound much the same. A thermometer reflects the environment whereas a thermostat affects the environment. A thermometer tells you how hot or cold it is. A thermostat shapes how hot or cold it is.
Followers of Jesus can be either of these instruments. We can reflect our world or affect our world. We can become captive to our surrounding culture so that we blend in. We are just like everyone else. Or we can be distinctive non-conformists who exemplify a different and better way of life.
Being thermostats doesn’t make us weird eccentrics or pious killjoys. It just means we bring something of Jesus’ values and teachings into our own lives. We point people to Jesus, and in so doing, we shape and reshape the world around us.
Christians have two options. We can let our surrounding world change us for the worse, or we can help change it for the better. Our text tells us the choice we need to make.