One genuine miracle equals a thousand sermons.
It was not through Jesus' preaching that the people recognised Him as the Son of God, but by the signs, wonders, and miracles which He constantly performed wherever He went.
We see in the Gospel of Mark 1:23 - 28 Jesus casting out the unclean spirit, (it was a demon who recognised first, that Jesus was the Son of God), the people were amazed, and asked themselves: "What is this? What new doctrine is this?" They were totally astounded by the authority Jesus used to cast out the evil spirit.
And we see in verse 28, that His fame spread throughout the whole region of Galilee.
Angus and Jill Buchan