C.S. Lewis, author of the widely beloved Chronicles of Narnia, wrote and talked extensively about morality. He was, in fact, a Christian apologist, which means he argued for believing in Christianity on a rational basis arising from historical and philosophical arguments.
He believed that there existed in the world a “universal morality”- that a universal right and wrong exists throughout the world, that people use their reason to identify right and wrong, and that our conscience tells us when we do right and wrong.
Regardless of your views about Christianity, I think we can appreciate Lewis’ effort to understand what it means to live a good life according to the highest Universal Morality. We should all strive to live a good, moral life.
In his essay, “Mere Christianity”, he offers the following passage about charity:
I do not believe one can settle how much we ought to give. I am afraid the only safe rule is to give more than we can spare. In other words, if our expenditure on comforts, luxuries, amusements, etc. is up to the standard common among those with the same income as our own, we are probably giving away too little. If our charities do not at all pinch or hamper us, I should say they are too small. There ought to be things we should like to do and cannot do because our charities expenditure excludes them. I am speaking now of “charities” in the common way. Particular cases of distress among your own relatives, friends, neighbors or employees, which God, as it were, forces upon your notice, may demand much more: even to the crippling and endangering of your own position.
For many of us the great obstacle to charity lies not in our luxurious living or desire for more money, but in our fear—fear of insecurity. This must often be recognized as a temptation. Sometimes our pride also hinders our charity; we are tempted to spend more than we ought on the showy forms of generosity (tipping, hospitality) and less than we ought on those who really need our help.
C.S. Lewis, Mere Christianity (New York: Simon & Schuster, 1996), pp. 82-83
Give, because you believe in a Universal Morality and that charity plays an important role in leading a good life.