They still didn’t believe in him, even though he performed many miracles in front of them. However, this fulfilled the prophecy of Isaiah, which said “Lord, who has believed what we have said? And who has witnessed the strength of the Lord?”

Isaiah explained why they were unable to believe when he said “He has closed their eyes and their hearts, so they could not see or understand, otherwise they would turn to me and be healed.” Isaiah said this when he saw His glory.

In spite of this, many people did believe that Jesus was the Messiah, even including some of the rulers. However they didn’t publicly admit this because the Pharisees had threatened to ban people from the synagogue if they did. They loved to get praise from men rather than getting glory from God.

JN 12:37-43