Al-e-Imran (The House of Imran) Sura 3: Verse 216
"But those who disbelieve after having believed, and then increase in their unbelief - their repentance shall not be accepted. They are the ones utterly astray. As to those who disbelieve, and die while they are disbelievers, there shall not be accepted from any of them even the earth full of gold, though they should offer it in ransom. For them, there shall be a painful punishment, and they shall have no helpers."