John 1:45-49
45 Philip found Nathanael and said to him, "We have found Him of whom Moses in the law, and also the prophets, wrote--Jesus of Nazareth, the son of Joseph." 46 And Nathanael said to him, "Can anything good come out of Nazareth?" Philip said to him, "Come and see." 47 Jesus saw Nathanael coming toward Him, and said of him, "Behold, an Israelite indeed, in whom is no deceit!" 48 Nathanael said to Him, "How do You know me?" Jesus answered and said to him, "Before Philip called you, when you were under the fig tree, I saw you." 49 Nathanael answered and said to Him, "Rabbi, You are the Son of God! You are the King of Israel!"
In this case, the miracle convinced this man Nathanael that Jesus was the Son of God, not just some prophet. The miracle led him to believe that Jesus was the Son of God. What merited a miracle to be shown to Nathaneal so that he could believe? I mean, the guy mouths of and says, "Yeah right. I'm sure the Son of God has come out of that scumhole Nazareth. LOL. Good one." Yet even with his sarcasm he still gets his miracle.
John 2:18-22
18 So the Jews answered and said to Him, "What sign do You show to us, since You do these things?" 19 Jesus answered and said to them, "Destroy this temple, and in three days I will raise it up." 20 Then the Jews said, "It has taken forty-six years to build this temple, and will You raise it up in three days?" 21 But He was speaking of the temple of His body. 22 Therefore, when He had risen from the dead, His disciples remembered that He had said this to them; and they believed the Scripture and the word which Jesus had said.
NKJV
In this case, Jesus' miracle prophesy proved the validity of his message, or word, to the disciples. It also proved that he was who the old testament said he was, which is the Son of God, the Christ. They needed for Jesus' prophesy to come true so that this miracle could prove to them that Jesus' word was the truth, and that he was who the Scripture (Old Testament) said he was.
So Adstar, you have to Admit that Jesus' miracles were not solely to attract people to hear the word. They also were done to PROVE THINGS AS WELL.