One who believes in the Son has eternal life, but one who disobeys{The same word can be translated "disobeys" or "disbelieves" in this context.} the Son won't see life, but the wrath of God remains on him."
The wrath of God ... New Testament passages regarding God's wrath are extensive; and far more is intended by them than God's displeasure at men who do not accept the Son and obey the gospel.  It has reference to the basic antagonism between light and darkness, goodness and evil.  The total race of men from Eden and afterward is a fallen and rebellious race, their fellowship with God having been broken by the fall of humanity; and God's face is set against fallen and unregenerated men.  He has appointed a day in which the unredeemable portion of humanity will be judged and punished, and when evil will be cast out of God's universe.  Mercy and hope for all are available in Christ; but it must be received and appropriated, and the penalty of rejecting the Son of God is the forfeiture of all hope.