The seven landmarks of Christian union are revealed by Paul in the first six verses of the fourth chapter of Ephesians: "I therefore, the prisoner in the Lord, beseech you to walk worthily of the calling wherewith you were called, with all lowliness and meekness, with longsuffering, forbearing one another in love; giving diligence to keep the unity of the Spirit in the bond of peace. There is one body, and one Spirit, even as also ye were called in one hope of your calling; one Lord, one faith, one baptism, one God and Father of all, who is over all, and through all, and in all." As long as these seven unities--one body, one Spirit, one hope, one Lord, one faith, one baptism and one Father--are maintained, it will be impossible for a divided church to exist. On the other hand, divisions will speedily disappear as soon as these seven unities are restored. I add the following chart of the New Testament church, which will serve as a summary and as a guide in the further study of this important subject: [Illustration: THE CHURCH THAT JESUS ESTABLISHED] CHAPTER III. THE CHURCH SINCE THE APOSTLES. _The Apostasy of the Church._ The apostolic unity of the church was maintained for about three hundred years. During this period the church endured the ten great, general persecutions directed against it by the world-ruling Roman Empire, which resulted in the martyrdom of almost all of the Apostles and multitudes of other Christians. Despite the opposition of the mightiest powers on earth, the church scored the most marvelous victories and was on a fair way to conquer the whole world for Christ. Satan, perceiving that his opposition to a united church under the leadership of Christ was fruitless, now tried to get within the church and to shear it of its power by confusing its counsels and dividing its forces. Christ said, "Every city or house divided against itself shall not stand" (Matt. 12:25), and Satan knew that if he could get Christians to exhaust their energies by contending with each other, their conquest of the world would be at an end. He filled the church with speculative philosophy, heathen idolatry and the worldly spirit in general. As always, he used the pride, vanity and ambition of individuals to accomplish his purpose. If fallible human leaders and their opinions could be put in the place of the infallible Christ and his teachings, the work would be done; because this would arouse the opposition of other ambitious human leaders and thus the church would be torn asunder and exhausted with internal strife and divisions. Alas that the church did not heed the earnest warning of Paul, "Now I beseech you, brethren, mark them which cause divisions and offences contrary to the doctrine which ye have learned; and avoid them. For they that are such serve not our Lord Jesus Christ, but their own belly; and by good words and fair speeches deceive the hearts of the simple" (Rom. 16:17, 18). The selfishness of leaders and the lazy,