Familiarity Breeds Contempt
They knew Jesus. He had grown up in Nazareth and had run the carpentry business. They had traded with him. He had made their doors and ploughs and coffins and mended their broken furniture. Everybody knew Mary and her family (we presume Joseph had died). Jesus had brothers and sisters, everybody knew their names. He was a real life ordinary man who worked hard and supported the family.
The problem was that His words were extraordinarily wise. Even at age twelve He astounded the religious experts in the temple. As a man He always seemed to have the right word at the right time and spoke as though He saw things from God's point of view - He did, because He was God in a human body. And His miracles amazed everybody. Nobody could explain them: how did He do them, who taught Him, where did He get such power from?
If they had seen Him in the light of the Scriptures which they professed to love, they would have realised that He is the Messiah (Christ) of God. But they saw Him through the lens of their experience of a nice local boy who became a skilful carpenter. They had wrong ideas about what the Messiah would be like too. They could not fit Jesus into their picture because they were not looking at Him from God's point of view.
The same is true today. People say Jesus is a good teacher: but He must be more than that because He used the ancient Name of God (I AM) as His own. The miracles all pointed to Him having the power of God, far exceeding anything that anyone has ever seen. If only people would look at Jesus in the light of Scripture they would see He is the Wonderful Counsellor, Mighty God and Prince of Peace described in Isaiah 9:6. Familiarity breeds contempt (an old English proverb) but it is very dangerous to dishonour Jesus. He said, "Whoever acknowledges me before others, I will also acknowledge before my Father in heaven. But whoever disowns me before others, I will disown before my Father in heaven." (Matthew 10:32-33).