The summary: short, sharp and shiny.
1. Speaking in tongues has nothing to do with the Biblical concept of salvation. Furthermore, speaking in tongues is a naturalistic, learned behaviour which predates Christianity.
2. The Bible is an ad hoc and contradictory assortment of mythical stories written and complied by men with questionable morals and no scientific understanding of the world they attempted to document.
3. Jesus was not divine. There is not one single piece of archaeological, forensic or documentary evidence that shows Jesus was anything more than a misguided Apocalyptic prophetic. Nothing was recorded about the man until decades after his death. Additionally, He falsely preached that God would intervene, destroy all evil, and establish a Kingdom of God on earth (rather than in heaven) and that this would occur during his lifetime. It didn’t.
4. There is no evidence that any God(s) exist. This absence isn’t proof, but it sure feels like a clue. The God documented in the Bible is arguably the most unpleasant character in all fiction: jealous and proud of it; a petty, unjust, unforgiving control-freak; a vindictive, bloodthirsty ethnic cleanser; a misogynistic, homophobic, racist, infanticidal, genocidal, filicidal, pestilential, megalomaniacal, sadomasochistic, capriciously malevolent bully.
5. Prayer does not work. There is not one single piece of documentary evidence that suggests prayer favors Christians any more than any other religion, or out performs the well-documented placebo effect.
6. Christianity doesn’t make sense. Original sin, Atonement, the Ascension, the Trinity, salvation and Hell are all man-made and non-falsifiable works of fiction.
7. Evolution is a unifying principle in biology, supported by overwhelming evidence. It makes testable predictions, withstands scrutiny, and is reinforced by discoveries across every scientific field. Creation lacks any scientific basis.
8. Bible Numerics [PDF] is a nonsensical and flawed pattern that can be found in any text.
9. British Israelism, pyramidology, and armageddon bible prophecies are elaborate fictions retrofitted onto history that require willful ignorance of archaeology, history, and probability.
10. Life is short. Dogma and guilt are debilitating.
Further reading
Easy – God is Imaginary
Medium – Why Christianity is False
Hard – Why I am not a Christian