Which is why World Vision U.S., along with most evangelicals today, have chosen to go with the third option, which is lowest common denominator pluralism. Rather than forming a community based on essential truths, adherents of this option choose which truths should be essential based on their desired community.
This is of course the opposite of how the church is supposed to function. As experience shows, ecclesial democracy pretty much always leads to compromise with error, acceptance of sin, and a general shallowing of the faith. This principle has been taken so far that an increasing number of evangelicals today have abandoned the task of theology entirely, declaring that all that really matters is some vague notion of following Jesus (when a person can make Jesus and the Christian life into anything he or she wants, who can possibly disagree with that?). When push comes to shove, evangelicals who take this route – which appears to me to be most evangelicals – will not be reliable allies in the culture wars.
Some evangelicals might say I’ve forgotten an option: evangelicals can just hold fast to the essentials of the faith while agreeing to disagree on the non-essentials. The problem with this is that sola scriptura provides no way for evangelicals to determine what is essential or not, which just pushes the problem back a step: evangelicals can have intractable disagreements about what’s essential, too. The wide range of reactions among evangelicals to the World Vision U.S. case is an example of this.
Lastly, an evangelical might protest that the Holy Spirit will guide them. Catholics agree that the Holy Spirit guides the Church, but, given sola scriptura, if two evangelicals sincerely and prayfully come to two contradictory conclusions about what the Bible says, how does one determine who is actually being led by the Holy Spirit and who is not? An evangelical might argue that the Holy Spirit will guide the evangelical community as a whole. But then how does one explain consensus in the evangelical community ever changing? In practice, this type of thinking ends up being more about people simply attaching the seal of the Holy Spirit to whatever decision they happen to come to.
All of this is to say, this World Vision U.S. case is not just about World Vision U.S., it also reveals deeper flaws in evangelical ecclesiology. Is this really the situation Jesus left for his followers? Is there a way forward that avoids both arrogant fundamentalism and shallow pluralism?
Yes: the Catholic Church. It's true that disagreements arise among Catholics just as they do among evangelicals, but, unlike evangelicals, the Catholic Church has a principled way to adjudicate them: Catholics believe that Jesus gave authority to the Apostles, who passed that authority on to bishops, who in turn passed that authority on to other bishops all the way to the present episcopate. While the Holy Spirit may be giving doctrinal direction to any given Christian, we know that the Holy Spirit is at least guiding the bishops. So when otherwise intractable disagreements arise, the bishops, led by the bishop of Rome as the successor of St. Peter, are capable of settling them authoritatively for the Christian community.
Someone might point out that self-identifying Catholics often disregard official Church teaching. That’s true, but such Catholics are bad Catholics. They are contradicting the principles of their own claimed Catholicism, namely, to follow the Magisterium. Evangelicals, on the other hand, remain entirely within their rights as evangelicals to disagree with other evangelicals as long as they think their beliefs are based on the Bible. Evangelicals who are convinced that Scripture doesn’t condemn homosexual acts may be wrong, but they are still good evangelicals.