Peter's Mistake (and ours?)

Here's a quote from Tim Keller's new book, Galatians For You. I'm halfway through, and a review will be forthcoming next week, God willing.

Peter's sin was basically the sin of nationalism. He insisted that Christians can't be really pleasing to God unless they become Jewish. But nationalism is just one form of legalism. Legalism is looking to something besides Jesus Christ in order to be acceptable and clean before God. Legalism always results in pride and fear, psychologically, and exclusion and strife, socially...

One way is to be sectarian. Every Christian group or denomination necessarily has many distinctions of belief and practices that have less to do with the core gospel beliefs and more to do with specific convictions about ethical behavior or church policy. It is extremely easy to stress our distinctions in order to demonstrate to ourselves and others that our church is the superior or best one.

Another way is to bring class-ist, nationalistic, or racist attitudes from the world into the church. We all know Christians who belong to classes, groups, or personality types that we had previously disdained in our lives outside the church... We may feel uncomfortable around people whose cultural emphases are different from ours. And we may respond to all this as Peter did in apparently well-mannered ways...

All this comes from not living in line with the gospel. Without the gospel, our hearts have to manufacture self-esteem by comparing our group with other groups. But the gospel tells us we are all unclean without Christ, and all clean in Him.

Lastly, the most subtle way to lapse into Peter's sin is simply to take our own preferences too seriously and endow with moral significance what is only cultural.

Galatians For You, Timothy Keller, The Good Book Company, 2013, pp. 54-55.