As we shall try to learn in the following pages, God--the three Persons of the Ever-Blessed Trinity--is always to be the first thought of the Christian warrior,--God, His Presence, His power, and His loving interest in our victory. But the well-trained soldier has an eye not to his own resources only; he seeks to learn something also concerning the Enemy he is to face. Next to the Presence of God, nothing is so necessary to the Christian soldier as to remember the presence of the Tempter; either in his own person or in that of one of his evil angels. Although God {2} has revealed nothing directly to us on the subject, yet His revelation concerning Satan's work is such that we can hardly escape from the conclusion that, as each soul has a guardian angel, so each soul has assigned to him by Satan an attendant evil spirit, whose whole business is to seek to lead the soul into sin. We see how in the conflict we have tremendous personalities to deal with, the Personality of the triune God,--Father, Son, and Holy Ghost,--and the Personality of Satan and his innumerable fallen angels, who, though finite and created, possess a scope and power which are, perhaps, so great that our human thought cannot compass them. But immeasurably below any of these as it is, our own personality must not be forgotten, for let it ever be kept in mind that _the issue of our individual battle depends on ourselves_. The laws of this war are such that on the one hand the powerful personal will even of the arch-fiend himself has no power to control us, except in so far as our personal will, acting with complete freedom, permits it; and on the other hand, the infinite personal will of God never operates so as to compel us, unless again our will yield freely to His call. Satan cannot control or influence us against our wills, and God, reverencing His image in man, refrains His power {3} and never forces man's love or service. The will of man is free, and this makes him the central factor in the spiritual warfare. II. _Not Peace, but a Sword_ In sending them forth on their first mission, the Prince of Peace declared to His awe-struck disciples, "I came not to send peace but a sword."[1] The world being what it was, the Kingdom of Peace was to be founded only by conflict. Those whom He sent forth to found His Church understood this principle, and everywhere in the accounts of their journeys and labours, as well as in the words of counsel they give their converts, there is the sound of warfare, "the voice of them that shout for mastery."[2] Everything indicates that the battle is fierce and desperate. Our Lord sends His message to the Seven Churches, and to each the reward is only "to him that overcometh."[3] We are warned of foes without and of traitors in the inmost citadel of our souls; of the "lusts which war against the soul";[4] "the law in our members warring against the law of our mind."[5] {4}