Not until some time after his baptism, when the Holy Spirit decended on him.
When John the Baptist saw Jesus, he said; "Behold the Lamb of God, who takes away the sins of the world".
This was a reference to the sacraficial lamb on the Day of Atonement described in Leviticus 16. As the one sent to prepare the way of the Lord, make straight his paths, John also knew that he had to die.
Speaking truth to power is always a dangerous proposition. John spoke openly about Herod's adulterous relationship with his brother's wife, causing Salome to ask for his head on a platter.
Jesus, as annoited son of David, was stating clearly his claim to the kingship of the Jews. The Pharisees understood this, and I'm sure Herod did also.