Vss. 18-21—Paul returns from his digression to resume the charge begun in verses 3-5. He adds something further here to what he had already said to Timothy—he reminds him that God had chosen him for this work. There were "prophecies" that had gone out before in regard to Timothy's gift and usefulness in the service of the Lord. Brethren had prophesied under the power of the Holy Spirit that God would use Timothy in His service. The elders recognized this too, and they gave him the right hands of fellowship (chap. 4:14). This is brought in here because Timothy might have raised a question as to his fitness for this work. However, knowing that God had spoken about him, by the Spirit, and that the elders had assented to it, he could rest assured that God would supply the grace to carry out the commission.
Holding Faith and a Good Conscience
Vs. 19—But there was something more; if Timothy was going to lead the saints in a line of conduct suited to the house of God, he needed to pay attention to the state of his own soul by “holding faith and a good conscience.” The moral state which Timothy was to labour towards in the saints was to be found in himself as well. Perhaps the reason why Paul does not mention "charity [love]" here, as he does in verse 5, is because it was obvious that Timothy dearly loved and cared for the saints (Phil. 2:20).
Firstly, Timothy needed to be “holding faith.” This is a reference to the inward energy of the soul's confidence in God—Timothy's personal faith. This needed to be held up bright and simple, not so that he could maintain the salvation of his soul—that was eternally secure—but to guard against doubts that the enemy would put into his heart that would disturb his confidence in God. It should not come as a surprise to us that Satan is trying to break down the Christian's faith—especially in those who are engaged in the service of the Lord. He often uses the trying circumstances of life to raise a question in our hearts as to whether God really cares and is providing for us. When doubts like this come—and they surely will—we will need to lift up "the shield of faith" and "quench" those "fiery darts" (Eph. 6:16) by remembering that "all things work together for good to them that love God" (Rom. 8:28). The first sign of a person's faith wavering under the pressure of the enemy in this way, is that he becomes discouraged in the path; let us be on guard (1 Peter 5:8).
Secondly, Timothy needed to hold "a good conscience." This is not maintained by never sinning, which would be unrealistic, because "we all often offend" at times in some way or another (James 3:2). A good conscience is held by regularly judging ourselves. Daily self-judgment, even in the smallest things, is essential to being kept from drifting onto the rocks and making spiritual shipwreck. The simple and honest confession of sin, coupled with true repentance, brings the soul back into communion with God (1 John 1:9). Keeping short accounts with God (not waiting for some other more convenient time to confess a sin to Him) is a necessary exercise in maintaining a right state of soul.
A "good" conscience is different from a "purged" conscience (Heb. 9:9, 14; 10:1-2, 12-14). The first pertains to our state and the second to our standing before God. When a person understands the finished work of Christ and rests in faith upon it, the Spirit of God comes to dwell in the person and gives him a purged conscience in regard to the eternal penalty of his sins. But a believer with a purged conscience can lose a good conscience by allowing sin in his life. He does not lose his salvation, but his communion will be interrupted, and thus, confession and repentance will be needed to regain it.
When a person puts away a good conscience by refusing to judge himself, as Paul says some were doing, he will make "shipwreck concerning the faith" (W. Kelly Trans.). J. N. Darby notes that the second use of the word "faith," in verse 19, refers to the doctrine of Christianity—the revelation of truth that was once delivered to the saints (Jude 3). As a rule, when the article "the," is in the text before the word "faith," the term is referring to the Christian revelation of truth. When the article is not there, it is referring to one's personal confidence and trust in God. Hence, making shipwreck concerning "the faith," means that a person veers off course concerning the truth. It may be ever so slight at first, but as time passes, the line of digression becomes more evident. The truth doesn't become shipwrecked; it is what the person holds as to doctrine that becomes defective. Since bad doctrines rarely travel alone, his theology will gather more and more erroneous points as time progresses.
For a Christian to sin is grievous enough; but what is worse, is the unwillingness to judge it. It is this that causes a person to get on a course that leads to shipwreck. It begins with allowing some sin, however small it may be, to go unjudged. As a consequence, he loses a good conscience and becomes uneasy about being constantly burdened about it. Almost invariably, he will alter his doctrine to accommodate and justify his course—but it will be to his own spiritual destruction, as far as his personal testimony regarding the truth is concerned.
Vs. 20—Two men ("Hymenaeus and Alexander") are mentioned as examples of believers who had made shipwreck of their Christian testimony. They serve as a warning to all who are not careful to hold "faith and a good conscience." These men came under the judgment of the Apostle and were "delivered to Satan that they may be taught by discipline not to blaspheme." They veered off course so severely that they had the audacity to teach things that were derogatory to the Persons of the Godhead—which is what blasphemy is. They were put out of fellowship (excommunicated) by the Apostle and left in the outside world where Satan could deal with them.
We also see in this that there is an aspect of practical salvation from the enemy of our souls by being within the assembly. These men were put outside of it, and thus, they lost this protection. J. N. Darby said, “In the assembly (when in its normal state) Satan has no power of that kind. It is guarded from it, being the dwelling place of the Holy Ghost, and protected by God and by the power of Christ. Satan can tempt us individually, but he has no right over the members of the assembly as such. They are within, and, weak as they may be, Satan cannot enter there. They may be delivered to him for the good. This may take place at all times ... . Within the assembly is the Holy Ghost; God dwells in it as His house by the Spirit. Without is the world of which Satan is the prince. The apostle (by the power bestowed on him, for it is an act of positive power) delivered these two men into the power of the enemy—deprived them of the shelter they enjoyed” (The Synopsis of the Books of the Bible – on chapter 1:21).
If we can take something from the meaning of the names of these two men as indicating their character, we would get a serious warning. "Hymenaeus," means, "wedding song." It implies that he had a lovely exterior in his personal manner. While we all should seek to be Christ-like in our character, if it is not real, it can be deceptive. There is a danger of becoming enamoured with individuals who speak in a lovely way and have a good demeanour. We could be taken off guard by it. Perhaps this man could present himself very well, but he held blasphemous doctrines! Let us be warned of such people. "Alexander" (It is probably the same person mentioned in 2 Timothy 4:14-15.) means, "man defender." This man was in direct opposition to Paul's ministry, which gives no place to the first man in the things of God. His name suggests that he resisted and opposed that line of truth and sought to give a place to man in the flesh in the Church of God.
In summary, Paul has insisted on two things that are essential to maintaining a good state of soul in the service of the Lord:
"Faith," which brings God in.
"A good conscience," which judges self and keeps sin out.
Without these two things, Timothy would not be able to "war a good warfare." He would be unable to stand before the enemy in the conflict of the faith—and neither will we.
Thus, the apostolic "charge" that Paul gave to Timothy was not to go out and put on a display of miracles, or to do something that would draw attention to himself; it was simply to lead the saints in a line of conduct that was befitting to the order of God’s house. This was to be accomplished by teaching the doctrines of grace that further God's present dispensation in Christianity, to the end that the saints would be found in a proper state and walking according to the due order of God's house. Timothy then, was to lay out the pattern of the house for them to follow; this is taught in the following chapters of the epistle.