Chuck Colson writes in Breakpoint:

I still remember my sadness on hearing that an old friend, and someone I believed was a sincere Christian, was leaving his wife of many years. I was shocked and disappointed. I wondered: How could this man, committed to both his spouse and his Lord, fall in love with another woman?

As essay by the late Sheldon Vanauken helps answer the question and reminds us that such temptations are all too common.

Vanauken, best known as the author of the powerful love story titled A Severe Mercy, also published a collection of essays called Under the Mercy, which explores these feelings.

In one essay called "The Loves," Vanauken describes how a Christian friend named John shocked him by announcing that he was leaving his wife to marry another woman. John explained his sudden change of heart by saying, "It seemed so good, so right. That's when we knew we had to get the divorces. We belonged together."

Vanauken then describes a conversation with a friend named Diana, who left her husband for another man. Diana defended herself with virtually the same words: "It was just so good and right with Roger that I knew it would be wrong to go on with Paul."

As Vanauken explains, both John and Diana were "invoking a higher law: the feeling of goodness and rightness…. A feeling so powerful that it swept away… whatever guilt they would otherwise have felt" for what they were doing to their families.