A white-haired, coffee-drinking teacher of mine once pointed out that a three-legged stool can’t stand with only two legs. He was right. Take away even a single leg and the stool comes crashing down.

This teacher told me the Christian life is like a three-legged stool. Take away prayer, the Bible or church, and the whole thing collapses. These things are essential.

Obedience and service are no less important. They’re roughly the same thing, but for this post I’ll use service to mean doing good things and obedience to mean not doing bad things.

Let’s start with obedience. God calls us to be free from sin—not mostly free, but completely free.

When I was younger, I thought sins were like parking tickets: they’re bad, but a few here and there don’t do much harm. I was wrong. Over time I discovered that sins are more like cancer cells: they’re deadly, and they grow.

Sin has a way of taking root like a weed. It hurts our relationships, destroying trust, shattering peace, undermining confidence and generally making a mess of things. Apart from damaging relationships, sin often brings other nasty consequences too.

God calls us to avoid sin completely because we’re truly more useful, more joyful and more content without it. If he tells us not to do something, it’s not because he’s a spoilsport. It’s because he loves us.

God lets us choose either to follow him or to go our own way. If we follow him, he always accepts us. If we go our own way, he lets us. It’s one or the other. Sin is antithetical to God—it’s everything he is not. We can’t have it both ways.

Service, I’m glad to say, is a much more cheerful subject than sin.

Loving God is his greatest commandment. What is his second greatest commandment?

Jesus said, “And the second is like it: ‘Love your neighbor as yourself.’ All the Law and the Prophets hangs on these two commandments” (Matthew 22:39-40).

Jesus also said, “A new command I give you: Love one another. As I have loved you, so  you must love one another. By this all men will know that you are my disciples, I you love one another” (John 13:34-35).

Service is all about loving others: donating money to feed families in Africa, playing Mario Kart with friends, listening when someone needs to talk or helping out around the house. It’s doing everything we can do to serve, encourage, bless, amuse, help and strengthen others.

It’s simple, but it’s not always easy. People can be awful. As Linus from Peanuts declared, “I love mankind—it’s people I can’t stand!”

In the end, though, loving people is an awesome paradox: those who are loved are blessed, and so are those who love. Everybody wins.

Next: Faith and Works