2 Timothy 2:3
You therefore endure hardness, as a good soldier of Jesus Christ.
I. THE SOLDIER GIVING UP THE DIRECTION OF HIS OWN ACTIONS AND EXERTIONS, GIVES HIMSELF UP TO THE SERVICE OF ANOTHER. The Roman soldier, to whose case St. Paul must be supposed particularly to refer, was nothing but a soldier. So it is with the Christian: he may not serve the world and his God together. He must either be all Christ's or none of His.
II. THE SERVICE INTO WHICH THE SOLDIER ENTERS IS FOR THE MOST PART A SERVICE ACCOMPANIED BY PERIL AND PRIVATION.
III. The third point of similarity observed in the conditions of the soldier and the Christian is, that EACH IS BOUND TO BE FAITHFUL IN THE DISCHARGE OF THE DUTIES OF HIS PROFESSION BY THE OBLIGATION OF A SOLEMN OATH. At the time St. Paul wrote, the Roman soldier, when first enrolled, took an oath to obey the commands of his emperor, and never to forsake his standard: and this oath was yearly renewed. A Christianised imagination found a parallel to this in the solemn engagement entered into at baptism, and renewed in the holy communion of the supper of the Lord, "obediently to keep God's holy will and commandments, and to walk in the same all the days of our life." For this very reason those two awful rites of our religion received from the primitive Church the name which they yet bear, the name of sacraments. Sacrament was the usual term for the soldier's military oath, and it was transferred by the ancients to baptism and the eucharist, because in them the believer, as it were, binds himself by solemn compact faithfully to serve in the spiritual armies under the orders of the King of heaven.
(W. H. Marriott.)
Parallel VersesKJV: Thou therefore endure hardness, as a good soldier of Jesus Christ.