‘My brothers, if any of you err from the truth.'
Mingled with encouragement and the vision of God, the whole of James' letter has been concentrated on bringing home ways in which ‘brothers' may err from the truth. Now like any good teacher he applies the lesson.
Truth is a central emphasis in the New Testament (which is why James saw it as so important in James 5:12). It was through belief of the truth that men would be begotten by God (James 1:18). To be filled with bitter jealousy and selfish ambition is to lie against the truth (James 3:14). Thus God's people are to be so bound by the truth that they do not need oaths (James 5:12). It is something that men must love (2 Thessalonians 2:10), and must obey (Galatians 5:7). It is something that men must demonstrate in their lives (2 Corinthians 4:2). It is something that must be spoken in love (Ephesians 4:15), and must be witnessed to (John 18:37). It is something which liberates (John 8:32) and must be openly revealed in a life of love (1 John 3:19). It is central to the whole Gospel, for the Spirit Who came is the Spirit of Truth (John 14:17; John 15:26; John 16:13), Who will guide into all truth (John 16:13). That is why those who believe also ‘do what is true' (John 3:21). ‘And one convert him (cause him to turn round).'
It is to be the concern of every brother that if he sees one of his brothers straying, he be concerned to ‘turn him round'. They are to feed and tend the sheep. That was not to encourage them to be busybodies and intrusive in men's lives, but in order to encourage them to prayerful and practical concern for the whole body of His people and their wellbeing (compare James 5:16). They were to watch out for each other, not critically, but prayerfully and with humility (compare Galatians 6:1-2).