A settled perspective developed in the Post-Reformation era, and then carried over into modern America, that the most important thing in Christianity is to believe correctly. Like all errors there is a serious grain of truth in this one. If "belief" refers to real faith, the kind of faith that "gives up one's own agenda" to follow Jesus and to depend on God's grace alone to save, both now and in the age to come, then this is all well and good. But we all know that this is simply not generally the case. In fact, it seems increasingly evident that the case is this—millions of Christians (?) in America believe something, who knows what, but understand little or nothing about vital, orthodox Christianity.
So I have to say this again and again: It is not enough to believe something, even the right things. You must understand and you must obey! Some of my postmodern friends embrace a type of progressive response to this "belief" problem that leads them to reject defined and articulated faith as the opposite of understanding and obedience. It is not. Real faith is always rooted in understanding, albeit simple understanding at the beginning of one's journey to Christ. But no one who believes in Christ should ever be left to this early simple understanding since true understanding leads to true, focused and profound action that is properly rooted in God's grace, not in our human pride or pursuit of self-fulfillment.
Christian leaders, about fifty years ago, spoke about "the younger churches" and "the older churches." Well, the younger churches have become older now and are growing all over the world, becoming the leading churches of the 21st century. And the older churches are either dying or changing. (I see no way for them to live but by change, in the right sense!) What is needed is to listen to a variety of Christian voices from all parts of the church so that we can do the kind of theology that "listens" well and "loves" deeply. Any other kinds of faith and belief fail to lead us to the true faith that understands and grows.