I believe there are a lot of Christians, myself included, who need to "go and learn" what it means to be more concerned with mercy than with conducting a church service. The idea of "sacrifice" speaks of our trying to please God with our worship. Too often we think God is impressed with our hymn singing and listening to messages, when we should be concentrating on winning people to Christ. And that doesn't mean getting the sinner into church where they can hear the Gospel! It means GOING out into the world with the Gospel. That's the kind of "service" God really enjoys.
We think "going to church" is the pinnacle of a Christian's doing what pleases God. I'd love for anyone to show me in the New Testament where it says, "go to church." I can show you a lot of passages where God says the church should "go" to the lost and tell them about Christ.