Sin has become commonplace among God’s people. We have become somewhat hardened to it, given the constant exposure we have to it through modern media. Sin is a problem in the life of a Christian, and unconfessed sin will hinder the prayer life of anyone.
Consider the following example of a young woman seeking counsel from a pastor’s wife. She said, "Jill, I’ve lost my joy, I’ve lost my peace, and I want it back."
"Where did you lose it?" I asked.
"That has nothing to do with this," she replied. "Help me to get it back."
"But where did you lose it?"
"I don’t want to talk about that."
But eventually she did talk about it. She lost it when she moved in with her boyfriend. That’ll do it. (Jill Briscoe, "Hanging Up Our Faith," Preaching Today, Tape No. 148.)