I’m sure that many of you have had the experience of dealing with thermometers and thermostats. The thermometer merely records the temperature. If it is seventy or eighty degrees it registers that and that is all. On the other hand the thermostat changes the temperature. If it is too cool in the house you simply push the thermostat up a little and it makes it warmer. And so the christian is called upon not to be like a thermometer conforming to the temperature of his society, but he must be like a thermostat serving to transform the temperature of his society. – Martin Luther King