Summary: When Jesus told Nathanael that He saw him under the fig tree, He was telling Nathanael that He knew everything about him, even the deepest longings of his heart.
John's Gospel is a very theological Gospel. Right from the beginning John wants us to understand the deep meanings of what Jesus said and did, and the significance of just who Jesus is. The opening of his Gospel makes it very clear that, "In the beginning was the Word, and the Word was with God, and the Word was God".
In John’s Gospel, there is no nice narrative of the birth of Jesus, like you find in Matthew and Luke, there’s no introduction to the beginning of the ministry of Jesus, as you would find in Mark's Gospel. If you’ll notice John’s Gospel starts off differently. John’s Gospel (or the Johannine Gospel) was written to give a deeper understanding to the simple story of what Jesus said and did.
John tells us how Jesus had begun to gather disciples to follow Him. Just a few verses earlier in this first chapter of John, Jesus walks towards John the Baptist. As He does so, John cries out, “Look the Lamb of God”! And after hearing this, two of John’s disciples follow Jesus. And these two are Andrew and Peter. John continues to tell us that the next day, Jesus finds Philip and simply says, “Follow me”. And John records that Philip went with Jesus.
As you read this text it ought to dawn on you that there must have been something very special about Jesus whom they never met until now—and yet they are instantly willing to leave what they know and possibly love in order to follow Jesus, whom up until now they did not know.
It ought to make you think: What was it that was so special about Jesus to these disciples? Was it His charisma? What was it about Jesus? Was it the way He carried Himself? Was it His confidence? Was it the way He taught and preached? These three men, Andrew, Peter, and Phillip had no problem following Jesus after meeting Him for the first time in their lives.
In fact Phillip saw something in Jesus that was so amazing to him until he had to run and tell his BFF by the name of Nathanael. John with his theological profundity tells us that, “Philip found Nathanael” and when he found him—he proceeded to tell him all about Jesus. And here’s what he said, he said, “We have found the one Moses wrote about in the Law, and about whom the prophets also wrote—Jesus of Nazareth, the son of Joseph."
Nathanael responded by to this good news in a negative, skeptical, and reactionary manner. Nathanael was a little prejudice, without thinking he uses a slur against Jesus because Jesus was from Nazareth, he scornfully asked, “Can anything good come out of Nazareth? In the eyes of Nathanael, Nazareth is quite an undistinguished place. This was a common behavior in the first century, people were normally judged based on where they grew up. If Jesus were from a more appropriate location—it’s possible Nathanael would have been a little more responsive to Phillip’s excitement, but Jesus was from of all places—Nazareth.