Every sale iplies a price, a
quid pro quo, an equivalent given to the seller in lieu of what he transfers to the buyer; but what equivalent can be given for life and liberty, both of which, in absolute slavery, are held to be in the master's disposal? His property also, the very price he seems to receive, devolves
ipso facto to his master the instant he becomes his slave. In this case the buyer gives nothing, and the seller receives nothing. Of what validity, then, can a sale be which desteroys the very principles upon which all sales are founded?
Blackstone
Selling one's self into slavery occurred throughout history. Slaves, such as skilled carpenters, sometimes would be allowed to buy themselves out of slavery in the old South by selling services to neighboring plantation owners.
Assume that the payment is to release me from some kind of crushing debt.