Good teacher

“A certain ruler asked Him, ‘Good teacher, what must I do to inherit eternal life?’ ‘Why do you call Me good?’ Jesus answered. ‘No one is good – except God alone.’” Luke 18:18-19
Some people misinterpret this verse to say that Jesus is denying the suggestion that He is God. That is not the case at all. He is, in fact, saying the opposite – picking up on what the man said, and pointing out that the ruler is in fact indirectly calling Him God.
The word ‘good’ here is the Greek agathos, which speaks of intrinsic goodness. There is another word also translated ‘good’, kalos, which speaks of outward beauty and moral goodness; in other words, good in appearance or for use. We see both words used in Matt. 7:18 – “A good (agathos) tree cannot bear bad fruit, and a bad tree cannot bear good (kalos) fruit.” The nature of the tree is what determines the kind of fruit it produces.
This is not a rebuke, but drawing attention to what he said. Jesus is the good teacher – just as He is the good shepherd (John 10:11). It was right that the man called Jesus ‘good’, and in so doing, Jesus notes that he is close to faith, because he recognised that Jesus was intrinsically good, because He is God.