Atheists, if I told you....

Impossible, because I cannot just decide to begin believing in something that I know to be a fictional tale of the supernatural. Also, I wouldn't want "eternal life" on someone else's terms. No gold-paved streets, angels, lying around on clouds playing harps, etc. for me. My idea of heaven would be this earth, unencumbered by disease, death, spiders, cockroaches, religious fanatics, and other assholes.

No, because I can't. Belief in something like God, salvation via Christ's vicarious atonement of our sins, heaven, hell, etc. is not simply an act of will. You rational mind will have to accept the proposition. Mine can't. I was raised in a Christian household, went to church every Sunday, and sincerely believed all this growing up. As I got older, and actually read the Bible, I started to have doubts, because some things didn't make logical sense to me. I spent years trying to hang onto my faith and justify it, but everything I read, including the arguments for belief in God just fed the doubts. My unbelief is not a matter of rejecting God; I disbelieve in God for precisely the same reason I disbelieve in elves -- I see no convincing evidence that they are real, and strong evidence supporting the proposition that they are not.

Let me put it in the form of a reductio ad absurdum: take your proposition, and substitute Jesus/God with Santa Claus. Could you do it? Could you make believe in Santa Claus. No, you couldn't. You know too much about the real world to maintain belief that a jolly fat man lives at the north pole, and once a year, somehow fills a flying sleigh with enough toys for all the world's children, and can deliver them in a single night. Your rational mind would never accept it. Same principle.