1) The bible claims that God sacrificed Jesus for our sins. (John 3:16, Romans 3:25, Ephesians 5:2, Hebrews 9:26) (This is ignoring Deuteronomy 24:16 and Ezekiel 18:20, which state that everyone is to be responsible for their own transgressions without anyone else dying for their sins, thus undermining the primary basis of Christianity.)
2) Since Jesus is God (2 Peter 1:1, John 10:30-33, and other verses), premise 1 means that God sacrificed himself.
3) A sacrifice involves the destruction of the entire being, including the spirit. This seems intuitively obvious especially for a self-sacrifice, since it's not much of a sacrifice if the martyr is guaranteed an eternity in heaven. The bible never directly specifies what constitutes a "sacrifice," but it seems to support this intuition.
a) In the entire bible, only humans are said to have been given immortal souls. (Ecclesiastes 3:11, 12:7, and other verses)
b) The bible allows animal sacrifice (several passages in Leviticus 1), but it condemns human sacrifice in the same breath as witchcraft, sorcery, fortune telling, and other forms of magic. (Deuteronomy 18:10-11)
c) Of all the things the bible forbids, why lump human sacrifice together with magic? It would require some type of occult power to sacrifice the additional element of the soul.
Do not be afraid of those who kill the body but cannot kill the soul. Rather, be afraid of the One who can destroy both soul and body in hell.
Therefore, the bible implicitly defines sacrifice as the destruction of the whole being, including the spirit.
4) From the above premises, God must have died with no afterlife.
Therefore, according to the bible, God doesn't exist.
When you think about it, this explains so much. Within the scope of the bible, it tells us why Jesus 2.0 fell somewhat short of godlike omniscience, actually having to ask why anyone would doubt that he's the same person who was just brutally murdered. (Luke 24:38) It explains why, aside from the occasional disembodied voice that only believers could hear for some reason, God never appeared or acted after the sacrifice. In Acts of the Apostles 1-14, angels always acted in God's place. Is it really more plausible that God still existed, but he was always busy? He had a little too much on his plate, so he had to delegate?
It also explains some current observations, like the fact that Jesus has never returned as predicted. It tells why God is credited with all those spectacular, unmistakable miracles in biblical times but has no noticeable effect today. It even gives us an explanation for ghost sightings: there's nobody to admit them into heaven.
I wish I could say I figured it all out first, but I think Nietzsche beat me to it. Still, at least I can do my part by spreading the good word. In fact, since the bible is already famous for being revised and edited throughout history, I'll go ahead and add a new chapter to the bible. Don't worry, it's only three verses:
There's probably no God. (Dawkins 1:1)
But if there is a higher power worth worshiping, he/she/it/they wouldn't want you to squander your life on fairy tales that don't even have happy endings. (Dawkins 1:2)
So stop reading this and enjoy your life. (Dawkins 1:3)