“I have not written to you because you don’t know the truth, but because you know it, and because no lie is of the truth.”
The Apostle John knows that God’s people know the truth for the witness of the Spirit of God within teaches them to discern all truth and untruth. They have been well grounded in the doctrines of the faith and so he is reinforcing what they already know and relating it to the issues of the day, as set out in his letter.
It is logical. If it is not the truth then it is a lie. It is that straight forward. However, it can be very problematic with some issues of the faith, as the water around them gets very muddy. It can be hard to discern a falsehood because of the context in which it is presented or because of the revered person who says it. People change their views on issues and can leave a former belief for another way of thinking. Beloved, we follow the living God and not other men or women.
It is so important to be grounded in the truths of God and not allow error to divert us from correct thinking, especially on the central issues of the faith. We all need to have a godly and proper point of view, for everything does not go!
“…knowing this first, that no prophecy of Scripture is of private interpretation. For no prophecy ever came by the will of man: but holy men of God spoke, being moved by the Holy Spirit.”
2 Peter 1:20-21
There are many in our days who are changing the basic truths of God and watering down the message of the gospel, so that what people put their faith in is not the real gospel, or even the real Lord Jesus. There is so much misrepresentation and unhelpful debate in media land, that it would be better to turn it all off and get alone with God and His Word. Our personal relationship with God is key and the filling of the Holy Spirit in our life is crucial to discern truth from error. We need to spend protracted periods of time in the Word of God and have a deepening understanding of its precepts and commandments. The Apostle is encouraging his sisters and brothers in Christ and bolstering up their grasp of the eternal word as it is revealed in the Holy Scripture. No other book will do and all other books are simply other people’s ideas about the one true book. Best to focus on the Scripture rather than opinion and people’s interpretation. Know the truth and cling to it…