(Vs. 12) In the preceding verse Paul speaks of the suffering, afflictions, and persecutions he had endured for preaching the gospel of Jesus Christ; and he adds, "ALL that will live godly in Christ Jesus shall suffer persecution." There are NO exceptions.
Satan, the world, and especially unsaved religionists hate the gospel of free grace and justification by faith alone. Going about to establish a righteousness of their own, they are opposed to the imputed righteousness of Christ and count as their enemies all who preach and believe it. Those who wish to be exempt from persecution must necessarily denounce Christ (John 15:18-21). All believers shall not be martyrs; but it is absolutely unavoidable that as soon as a true knowledge of grace and a zeal for the person and work of Christ is manifested by a believer, it kindles the rage of Satan and ungodly men. By persecution, slander, murmuring, or some other method, trial will come!
(Vs. 13) By "EVIL MEN" are meant not openly profane sinners of the world nor wicked men in general, but wicked men UNDER A FORM OF GODLINESS (in the pulpit and the pew) who are bent on seducing and deceiving others to follow their false doctrine and gospel of works (Matt. 23:15; 24:11, 24). In the last days these religious hucksters and jugglers of truth shall wax worse and worse, deceiving many and being further deceived themselves (II Thess. 2:8-12). It is not because error is stronger than truth nor because Satan is more powerful than the Spirit of God, but because natural men are more inclined to embrace error and will embrace that which agrees with their carnal nature (John 5:42-44).
(Vs. 14) Although wickedness prevails, false doctrine abounds, and the enemies of Christ rise up in religious circles, you continue in the doctrines of Christ, which you have learned and have been convinced of by the Word of God. You know that what you have received was not of men, but the gospel of grace has GOD AS ITS AUTHOR. We dare not adopt all that is taught nor defend indiscriminately all we hear, but only that which is according to the scriptures.
(Vs. 15) From your childhood you have been taught the scriptures. The Jews very early taught their children the scriptures (II Tim. 1:5). Men are not wise of themselves but are without understanding of spiritual things (I Cor. 2:14). The scriptures are able to make men wise and knowing in this respect, for they testify of Christ (John 5:39). The Holy Spirit uses the Word of God to convince of sin, to reveal Christ's person and work, and to beget life and faith in the sinner (Rom. 10:17; I Peter 1:23; James 1:18). Wisdom to salvation lies not in the knowledge of the law, rituals, and ceremonies; but true wisdom to salvation is in a spiritual knowledge of Christ, which comes from the scriptures (Luke 24:44-48).
(Vs. 16) "All scripture;" the whole of it (both the Old Testament and the New Testament) is verbally inspired by God, or God-breathed (II Peter 1:20-21). The scriptures are commended by their Divine authority. God used men to write His word. These men boldly wrote what the mouth of God spoke! Whoever wishes to profit in the scriptures must, first of all, lay down this as a sure and settled point: that the scriptures are not the words, doctrines, and writings of men only, but were dictated by the Holy Spirit!
Having settled this point we can go to the next; therefore, the scriptures are profitable for doctrine, reproof, correction, and instruction in righteousness.
"DOCTRINE," for discovering, confirming, and teaching all doctrine concerning God, man, redemption, eternal life, and all subjects concerning our lives in every area.
"REPROOF" of errors, heresies, and false teachings concerning the gospel.
"CORRECTION" of attitude, spirit, and practice in believers.
"INSTRUCTION IN RIGHTEOUSNESS" in every branch of duty incumbent upon men. Whether with respect to God or men, the scriptures are a perfect rule of faith and practice.
(Vs. 1.7) All scripture is given that the believer may grow in grace and the knowledge of Christ and be well-fitted and thoroughly equipped for every good work.