Assuming that we have our spititual eyes open, we know this life is a battle: warfare between between good and evil. One who does not know this will find it out or perhaps is already down and out. The battle is spiritual and the battlefield is the mind. Eph.6:12. From the Bible and from my own experience I write the following:
The Scriptures, Eph.6:13, compare the believer to a contestant in a gladiators arena, viewed by heaven and earth, “having done all, stand”, the enemy under our feet in defeat.