Most of people here are Christian, while I am Jewish. Yet like Pascal's Wager, this can be a universal question. If you had a chance to give up your soul to eternal suffering for a temporary benefit, would you?
Well, there is no heaven. There is no Hell. There is no purgatory. The part of me you might call a "soul" cannot be "bought" or "sold" or even contained outside of the body it occupies in this existence. So, make me an offer.
If the devil ever appeared and asked me to sell my soul that would mean he existed and so did souls and so did heaven and so did hell. So no, nothing could ever be worth an eternity of suffering. It's the same reason as devil worship being silly, if you really believe in the devil, why should you back a loser Now I might sell it for immortality, because then I'd never die, and so never have to pay up, but the devil would undoubtedly have some clever way to screw me, as he always does. Like give me a very painful disease which drugs would not counteract or palliate. (hell, that's not even clever, and I was really considering the immortality thing for a minute. Good thing I wasn't talking to Old Scratch. Or was I?)
A soul can't be sold, so if someone is wiling to pay for me for what they believe is my soul, I'm happy to sell. However, I'm also an honest person. I would not sell my soul to two people, as that would be fraud. So, I'll take $1 million, as I'm not likely to receive a better offer and I feel if I take less, someone might offer $1m.
I have seen no evidence for the existence of a soul. But if it did exist, and selling it would mean eternal torture vs eternal "bliss" (whatever that would look like), there is no price that could cover that difference.
No, sell it to who? Either there is or isn't a soul - and is or isn't someone to sell it to. The actual question is a bit different. If someone said "I'll give you ______ if you sign this paper that I own your soul," would you if you believed the person would do his/her end of it in payment. I wouldn't. It just seems unwise. The "abundance of caution," bad karma and possible weird psychological effects too.
Maybe to some principled people it would be better to oppose a tyrant and suffer than give the tyrant what he wants. Old Scratch? Was that a South Park reference?
The devil appears to most people many times a day, and yet we do not recognize him/her/it. Thus many people do sell their souls for worldly pleasures.
Generally it is a different type of deal. For instance a motorcyclist gets pleasure of riding high -- although he/she knows that accident due to riding a motorcycle on drugs may be counted as suicide.
If The Devil promised you 40 years of worldly bliss at a cost of 4,000 years of suffering 1,000 times greater then maximum suffering anyone could suffer during life, what would you do?
Many people kill themselves. Irrational choices by some people sometimes can be counted on. But it is a bit odd to talk about selling something we don't even know exists. How do you sell your soul anyway?
All people must obey certain core commandments -- the Seven Laws of Noah are accepted by Judaism, Christianity, and Islam. As a Jew I have more Laws. An example of selling one's soul cheaply would be becoming a thief to sustain a drug habit. A person who becomes a millionaire by a massive charity fraud also sells his/her soul -- but for a good price.
That's a lousy deal for such a high quality soul. I'd go for at least 100 years and waterboarding....maybe.
But many people would more then agree to 40 years of worldly bliss at a cost of 4,000 years of suffering 1,000 times greater then maximum suffering anyone could suffer during life.