As we continue to lead God's people in an increasingly post-Christian environment, common misunderstandings about our faith can create unhelpful distance between ourselves and the people we are trying to reach.  It is my hope that the insights in this series of posts help bridge that gap in a way that promotes fulfillment of the Lord's Great Commission.
When researchers test their hypotheses in view of establishing theories, they will set forth various predictions that should come to pass if their hypotheses are correct.  If their predictions do not come to pass, the theory may need adjusting or the assumptions that led to these predictions may be faulty.  For the present discussion, here's what this means.
Non-Christians will sometimes point to the moral failure of a Christian leader as evidence that Christianity itself is a sham.  As Christians, we would immediately recognize the disastrous effects of moral failures among our leaders, and one of these certainly is the impact these failures have on the unbelieving community.  The idea, though, betrays a myth about Christianity - a faulty prediction.
The faulty prediction would be: If Christianity is true, Christian leaders will never fall.  This is a non sequitur.  This opens up the issue of theory versus practice.  In theory, Christ always provides a way to escape temptation, so we should be able to live our lives without sinning (1 Cor. 10:13).  In practice, though, there are many times that the spirit is willing, yet the flesh is weak..  In such times, we do not take the path of escape that God has provided.  The Bible is very clear that believers retain a sin nature up until such time as we receive our glorified bodies (Phil. 3:21, e.g.).  Until then, we will face a war in our members (Rom. 7:23 ff.).  We have choices.  We can put on the new man or the old man (Eph. 4:22-24).  The reality is that the truth of Christianity does not hinge on the morality of Christian leaders.  The fact that we retain this sin nature almost means that all of us are hypocrites to some degree.  Even though we are not always true to our own profession of faith, the weakness of our sinful flesh does not mean that the Christian faith is hogwash.  Christian doctrine does not pretend to teach that Christians, once saved, will never again sin (John 13:10).  Therefore, to dismiss Christianity on the grounds that some of its proponents fail is logically unsound.  
That said, let us provoke one another to good works (Heb. 10:24).  Let us give the more earnest heed to the things which we have heard, lest at any time, we should let them slip (Heb. 2:1).  And let our light so shine that men may see our good works and glorify our Father which is in Heaven (Matt. 5:16).  The more our walk matches our talk the less explaining of our failures we will have to do before unbelievers and the more Gospel-sharing we will be able to pursue (1 Cor. 9:27).

An angle that few if any seem to take is to examine the issue from the perspective of overall church unity.  It just so happens that I am guiding my church through 1 Corinthians in this modern situational context; so church unity is obviously on the brain.  Two questions emerge: (1) Can you have spiritual unity without political unity? and (2) What does preserving spiritual unity look like in such a politically divisive age?