He confessed, and didn't deny, but he confessed, "I am not the Christ."

 1:43-51 On the next day Jesus determined to go away to Galilee; and there he found Philip. Jesus said to him: "Follow me!" Now Philip came from Bethsaida, which was the town from which Andrew and Peter came. Philip went and found Nathanael and said to him: "We have found the One about whom Moses wrote in the law, and about whom the prophets spoke--I mean Jesus, the son of Joseph, the man from Nazareth." Nathanael said to him: "Can anything good come out of Nazareth?" Philip said to him: "Come and see!" When Jesus saw Nathanael coming towards him, he said: "See! A man who is really an Israelite! A man in whom there is no guile!" Nathanael said to him: "How do you know me?" "Before Philip called you," said Jesus, "I saw you when you were under the fig-tree." "Rabbi," answered Nathanael, "you are the Son of God; you are the King of Israel." Jesus answered: "Do you believe because I said to you, 'I saw you under the fig-tree'? You will see greeter things than these." He said to him: "This is the truth I tell you--you will see the heavens opened, and the angels of God ascending and descending on the Son of Man." 