Today Pat refers to 1 Peter 5:8, "Be of sober spirit, be on alert. Your adversary, the devil, prowls around like a roaring lion, seeking someone to devour." NASB
What does it mean to be "vigilant"? One definition states, "to be keenly watchful to detect danger". As Christians we must always be on the watch for the health of our spirit and the spirits of others, just as we always watch our battle-buddy's six on the battlefield.