Timothy was called to teach the faith of Christ in love; but in doing so he came up against those who were giving false teaching or useless teaching. He also came up against those who professed to be teachers but had no real understanding at all.
There were false teachers in Ephesus, as there were elsewhere (see Paul's warning about them in Acts 20: 29, 30). Their teaching was in direct contradiction to the life-giving gospel of Jesus Christ that Timothy had received, and should pass on to others. (Compare Galatians 1:6-10.) Their work had to be opposed, as truth must always oppose error. In our different denominations none of us has perfect understanding of the truth of Christ, but when we agree about the great essentials of the gospel we can work together, support one another and learn from one another. On the other hand, there are some who call themselves Christians who have gone astray in the very essentials of the gospel. There are those, like the Jehovah's Witnesses, who deny that Jesus is God. There are those who deny that Jesus rose from the dead. There are others who deny that the truth of Christ is good news of salvation for sinful men and women. We must be sure of the essentials of the truth, and so be able to defend the truth against those who oppose it.
Timothy also often met those whose teaching was not so much wrong in itself, but it emphasized things of no importance. They argued about 'myths and endless genealogies'. They gave their own meaning to names and lists of names in the Old Testament. They had their own ideas about many things, and they tried to argue from the Scriptures about these things. But they neglected the great purpose of God which He had revealed in Jesus Christ (the 'divine training', verse 4). That teaching we received by faith, and as we try to understand it more, it leads us to a stronger faith. We must guard against anything that makes us neglect the great truth of God in Christ. It may not be 'myths' or 'endless genealogies' that turn us aside from the important things. It may be debates about details of church organization, about collecting money, or about other things important in themselves, but not the things that matter most.
Then there were others who wanted to be called teachers, but their talk also was vain and valueless, because they had no understanding, The work of a teacher is a very important one. But if we teach others, we have a great responsibility ourselves to act on our teaching (see James 3:1, 2). Moreover, we can only teach what we ourselves understand, and all the time we must be growing in understanding (see 2 Peter 3:18). We cannot give out constantly in the service of Christ, without daily receiving new teaching from God's Word. We cannot teach unless we are learning. If we are not going on learning, our words will be empty words, words without understanding.
In contrast with these wrong teachings, there is the true teaching of Christ. Its character Paul describes as 'speaking the truth in love' (Ephesians 4:15). False teaching is teaching without love because it does not honour God who alone is worthy of all praise and love and service. Some other teaching is not false but it is useless, because it does not go further than the mind, and does not lead us into love for other people. The true teaching of Christ should lead us to love Him, and to love our fellows for His sake. Such love comes from 'a pure heart and a good conscience and sincere faith'. That means that when we hold to the great truth of God in love, we will have a pure and single desire to serve Him; we will have found the way to forgiveness of sin through the sacrifice of Christ for us, and the way to keep our consciences clean by daily repentance and fresh cleansing through the blood of Christ; and we will have sincere and lasting faith in the Lord Himself
O God, Thou hast given us the truth in Jesus Christ, and called us to teach it to others; fill us with love, and help us to grow in understanding, that we may keep ourselves and those whom we teach from what is false and worthless; and may we walk more closely every day in the ways of Thy truth and in the direction of Thy purpose, through Jesus Christ our Lord. AMEN.
Notes. 1. Verse 3 seems to mean that Paul left Timothy in Ephesus when he himself went on to Macedonia. We do not know of a time when the apostle did this on his missionary journeys. If he had a time of further missionary work between a first and second imprisonment in Rome, there would be no difficulty in fitting this incident into that period (see Appendix).
2. The word which is translated 'divine training' in verse 4 is the same word in the Greek New Testament as in Ephesians 1:10 and 3:9, where it is translated as 'plan'. It is God's 'arrangement' of things for His world, His plan and 'purpose' that Paul is speaking about here also.
Further Study.
1. Look up singular passages in the Pastoral Epistles that speak of the kind of useless teaching that verse 4 mentions. See especially 1 Timothy 4:7; 6:4; 6:20; 2 Timothy 2:14, 16, 23; 4:4; and Titus 1: 10; 3:9.
2. Consider other New Testament passages that give teaching concerning 'love' and the connection between 'faith' and 'love' .See especially 1 Corinthians 13; Galatians 5:6, 22; James 2 and 1 John 2: 3-11.