Paul writes the following in his first letter to the Corinthian church:
Were you called while a slave? Do not worry about it; but if you are able also to become free, rather do that. For he who was called in the Lord while a slave, is the Lord’s freedman; likewise he who was called while free, is Christ’s slave. You were bought with a price; do not become slaves of men. -1 Corinthians 7:21-23
As a modern American, when I read "slavery", the following sorts of things scroll through my head:
The movie Amazing Grace, with all its graphic descriptions of Africans being shackled and crammed into tiny ships where they waded in puke and dysentery for weeks prior to having rope shoved up their rectum so they could bring more profit when they were sold at the auction
Israelites conquering their enemies and turning them into slaves
Stuff I've heard about how "back in Bible times" slavery was more like indentured servitude... poor people would make an agreement with a land-owner to work for them for some period of time, and received food and shelter in return.
Commentaries I've read that apply New Testament passages about slavery to modern employment arrangements
I'm not looking for an overview of all of the different types of "slavery" throughout history, but needless to say, there's a lot swimming around in my head on this topic. My question here is pretty simple: what was Paul referring to in 1 Corinthians 7:21-23 when he spoke of "slaves"? A good answer will include some historical context, some clues from the literary context, and perhaps some support from other relevant places in the New Testament (esp. Paul's writings.)
And, if you're itching to take it a step further, does Paul's situation have any direct, modern, Western equivalent? (I.e. would Paul urge the Engineers at Intel to quit their jobs and "free" themselves from their "slavery"?)