Dinesh DSouza has resigned as president of The Kings College, a leading Christian liberal arts institution in New York City. While he denies any moral wrongdoing, his conduct regarding his marriage and fiance (he is married to one woman, engaged to another) has raised serious questions about his capacity for spiritual leadership.

At lunch today, I learned that a pastor in my home state of Washington recently admitted that he had had a decade-long affair with a woman in his church.

My former pastor carries in his Bible a list of all his friends from seminary who have fallen from the ministry due to sexual sin. Its more than 20 names long.

Whatever the dynamics, adultery is a plague in the leadership of the church. According to psychologist Mark Laaser, author of Healing the Wounds of Sexual Addiction, over the past two decades adultery has become "an escalating crisis in the church" so that "rarely a day goes by that I don't get a call about a 'fallen' pastor."

Why? Being a pastor is hard and lonely. It requires time by oneself in intensive study, which by definition is draining. This often is augmented by frequent acquaintance with the broken things of life, from substance abuse to officiating at a childs funeral. Pastors are needy, as are many women in our churches. The quiet of a church mid-week provides opportunity. And, thus ...

However, there is never a biblically justified excuse for sin. Christian leaders must must build in safeguards to discourage the likelihood of infidelity. Accountability partners, working hard to have a vibrant, affirming relationship with ones wife, having an open Internet history that reliable friends can check at will: These are a few of the tools faithful men can employ to remain morally pure.

Yet with all of that said, Scripture gives only prescription for dealing with sexual temptation: Flight. Heres what Joseph did when the wife of his owner Potiphar attempted to seduce him: She caught (Joseph) by his garment, saying, Lie with me! And he left his garment in her hand and fled, and went outside (Genesis 39:12).

Similarly, Paul the apostle tells his young disciple Timothy, Now flee from youthful lusts and pursue righteousness, faith, love and peace, with those who call on the Lord from a pure heart (II Timothy2:22).

Dont try to rationalize away the potential for temptation. Dont say, Oh, were just friends and having lunch together is harmless. Dont share things of the heart with a woman other than your wife. Flee.

A few years ago a friend told me of a woman who seemed to want to have an affair with him. He related that she had come to the door of his office and engaged in a flirtatious conversation with him.

I said to him, You should have said, I cant talk with you now, and shut the door. He responded, I couldnt do that, as he was concerned with rudeness. I replied, Yes, you could. Better to be rude than ruin your marriage.

Adultery is the success of self-exaltation: For the sake of my perceived happiness, Ill do what I want, whoever it hurts. You shall be like gods, the serpent told Eve. He still whispers this to all of us, including to men who put their desires ahead of their Lord, their wives, their children, their ministries, their friends, and their honor and the honor of the God they profess to serve.

Christians should pray for Dinesh DSouza and his family as they begin a new journey in their lives, and for others each of us know who have collapsed into infidelity. And Christian leaders should feel a slight shudder in their souls as they pray: None of us is immune.

When adultery walks in, writes theologian Woodrow Kroll, everything worth having walks out.

Everything. Pretty high cost, that.