Yet matters of doctrinal purity require making a clear stand, precisely because an unbelieving world watches us so carefully. When they see Rick Warren offering them a "salvation" without repentance (for example) as he rakes in the bucks selling his Purpose-Driven merchandise, some of them undoubtedly conclude that his "purpose" has more to do with himself than with honoring the Lord. Or (as another example) when Brooke Boon combines the Hindu practice of yoga with Bible reading, surely some non-Christians see the obvious contradiction.
Non-Christians aren't stupid! Many of them can see our doctrinal compromises with their worldly philosophies. And, while they may in some respects welcome those compromises, they learn that we don't take the Lord or Scripture very seriously.
Consider the possibility that those who care enough to challenge people like Beth Moore or the Gay Christian Movement (just as two instances) might show an unbelieving world that Christians really do care about presenting truth accurately. Could we even show, by standing against teachings and practices which contradict or distort God's Word, that we love people enough to warn them when they drift into doctrinal error? Maybe the courage to tell other believers that a popular teacher or trend leads to deception might demonstrate to non-Christians that we love truth and desire for our brothers and sisters to follow it faithfully.
For many years, my mom firmly believed my church blindly followed the pastor. Often, she accused church leadership of brainwashing me. But as she saw me study Scripture for myself and consequently challenge the leadership's Charismatic teachings, she gained new respect for my spiritual integrity. Similarly, when John and I left the church that had supported us through our first twelve years of marriage, Mom respected us for our doctrinal stand. So did other non-Christians that knew why we left. As strange as it seems, non-Christians appear comforted by the thought of Christians choosing to follow Scripture, even when doing so goes against their church.
Additionally, and perhaps more to the point, we can't assume so much responsibility for whether or not non-Christians come to salvation. If God, in His sovereignty, elects someone to salvation, even our worst blunders and stupidest sins can't block the Holy Spirit from reaching them. He uses us to proclaim His Gospel, yes, and most assuredly commands us to live lives that reflect His holiness. But, as John remarked during supper last night, we blaspheme Him when we suppose that our actions can result in causing anyone to miss out on salvation.
So, even though some disagreements among Christians expose our immaturity by displaying our silliness, taking stands for doctrinal purity communicates to the world that we hold God's Word in such reverence that we will contend for it, even against those within our ranks. Our commitment to truth won't prevent the Holy Spirit from regenerating anybody, and may even help people respect us for doctrinal integrity.
3 Beloved, although I was very eager to write to you about our common salvation, I found it necessary to write appealing to you to contend for the faith that was once for all delivered to the saints. 4 For certain people have crept in unnoticed who long ago were designated for this condemnation, ungodly people, who pervert the grace of our God into sensuality and deny our only Master and Lord, Jesus Christ. ~~Jude 3-4