john 1:48 Nathanael saith unto him, Whence knowest thou me? Jesus answered and said unto him, Before that Philip called thee, when thou wast under the fig tree, I saw thee. - Free Bible Online

      48. Whence knowest thou me--conscious that his very heart had been read, and at this critical moment more than ever before.
      Before Philip called thee--showing He knew all that passed between Philip and him at a distance.
      when . . . under the fig tree, &c.--where retirement for meditation and prayer was not uncommon [LIGHTFOOT]. Thither, probably--hearing that his master's Master had at length appeared, and heaving with mingled eagerness to behold Him and dread of deception--he had retired to pour out his guileless heart for light and guidance, ending with such a prayer as this, "Show me a token for good!" (See on Lu 2:8). Now he has it, "Thou guileless one, that fig tree scene, with all its heaving anxieties, deep pleadings and tremulous hopes--I saw it all." The first words of Jesus had astonished, but this quite overpowered and won him.

JFB.