A congressman who was shot down and captured in Vietnam says religious faith is essential to a prisoner of war's sanity. Republican Congressman Sam Johnson of Texas says "the whole country's praying" for the U-S troops now being held captive in Iraq. Johnson spent nearly seven years as a P-O-W -- half of it in solitary confinement -- and recalls that the first few days are the worst. The congressman says that while his mother made him go to church every Sunday, he only "really came to know the Lord" when he became a prisoner of war. He says he never prayed so hard as when the North Vietnamese stood him up in front of a firing squad.