Christians didn't own slaves.
Bullshit. Not only did they own slaves, they used the bible to justify the practice of slavery. You can use all the fuzzy definitions and obfuscations you want and it cannot, and will not change the fact of the matter than there have been many, many christian slave owners and that the bible does not condemn slavery, and in some cases can even be percieved as advocating it.
A slave was someone who couldn't pay off a debt with money, so they paid it off with work.
So what was the debt owed by the people who were conquered and subsequently enslaved? The only limitations to slavery that are found in the bible is that jews should not enslave their fellow jews, and if they do then they must release them after 7 years unless they use the biblically proscribed method of tricking them into remaining a slave.
When the debt was paid, the slave was free.
Except the debt would never seem to get paid off. What you are describing is indentured servitude and that is not what is described in the bible. Now some slaves may have been enslaved for their debts, but certainly not all of them and certainly under much harsher conditions than you are now implying.
And every 50 years, all slaves were given a clean slate wheither they still owed money or not. Even if they had sold their property to pay off a debt, the property was given back
And yet you provide no proof for any of you claims other than you said so. Also, Every 50 years? Life expectencies were short enough at that time that you could realistically go throught close to 3 generations, and the person who owed the debt, and the holder of that debt were both likely long dead unless the debtor "bought" the slave when they were both toddlers.