I've had a lot of thoughts lately on the difference between believing something and living something. It's a problem probably best explained by turning to the letter of James in the New Testament.
In my own life and in much of my observation of many evangelicals, we seem much more concerned with the doctrinal underpinnings held by a person, church, or Christian organization than the life they live and works they do. I used to judge a good church by their doctrinal statement. I used to judge a good Christian by their particular understanding of salvation or the Trinity, or some other doctrine.
I'm not questioning whether or not right doctrine is important. It is of critical importance. But it isn't of only importance, and maybe not even ultimate importance.
James writes, "You believe that God is one; you do well. Even the demons believe—and shudder!" (2:19)
He is claiming that the demons are orthodox. Their doctrinal statement is right. They believe God is One, and to say God is One is to agree with the most crucial statement of belief in the Old Testament, the Shema in Deuteronomy 6:4.
This verse is in the context of James' claim that "faith without works is dead." So James is using the demons as a powerful illustration: though the demons have their doctrinal ducks in a row, that isn't enough. James insists that a saving faith, a living faith, is also a working faith. That doesn't mean that works must be added for people to be justified before God, but that one must possess the right kind of faith to be justified before God. And the right kind of faith is active in mercy, love, compassion, service, preaching and so on.
Typically this teaching is brought up to point out that some people claim to be Christians but really aren't unless they live like it. That's true. When reversed it makes sense too. People who do good works of some sort but don't hold to a faith in Christ aren't Christians. Another helpful application.
But something seems wrong.
There are people who claim to have a real faith in Jesus and who live consistently kind of life Jesus lived and taught. They are loving and merciful and they are also passionate about Jesus, God's Son. But because they might waver on a doctrinal point or two, evangelicals will deem them unsaved. Or maybe they view an ethical application of biblical teaching differently, and so evangelicals will judge them as maybe not truly Christian.
Yet in my experience, one of the chiefest of sins of evangelicals is our lack of works. We claim our "eternal security" all day long, but fail to grab the ladle that serves the poor or open our homes to those in need. Our understanding of works too often consists of tithing, not doing a ton of things (including many things that aren't prohibited in Scripture), and on occasion trying to give a tract to someone or invite them to church.
And so the question comes: Who are our true brothers or sisters in Christ? I believe where it isn't obvious, we should be accepting of all who claim it and live it (faith that is fruitful). We may disagree publicly with doctrinal error, and point out ethical discrepancy, and open our Bibles to argue for the best explanation of the truth. But that doesn't mean we shouldn't consider ourselves One Body in Christ.