Here are Scriptures from John`s Gospel showing that God sent His Son to earth--and why He sent Him:  "For God didn`t send his Son into the world to judge the world, but that the world should be saved through him. He who believes in him is not judged. He who doesn`t believe has been judged already, because he has not believed in the name of the one and only Son of God. This is the judgment, that the light has come into the world, and men loved the darkness rather than the light; for their works were evil. For everyone who does evil hates the light, and doesn`t come to the light, lest his works would be exposed. But he who does the truth comes to the light, that his works may be revealed, that they have been done in God" (John 3:17-21).

Read that quote in its context here.