John continues in his passionate desire to help his readers (us!) know that we can know some things for sure. In particular here he is equipping us to know how to discern truth from error. Verse 2 is a very straightforward question we may ask of any teaching that comes our way - 'what is your view of who Jesus is?' The point of the paragraph, however is not strictly to give us an intellectual test question. Rather, the heart of his message is in verse 4 where he reminds us clearly that 'we are from God' (we belong!), and that therefore the One living inside of us (the Holy Spirit) is much greater than any false teaching we might encounter! This is where our confidence comes from! Not from our ability to figure it out, but from the Spirit whom God has given to His children! Praise His Name!