"I do not believe that he or Christianity endorsed slavery, however, that was the times and age that he was living in, and even today we still have slavery in parts of the world. I think Paul was trying to tell the slaves not to make matters worse and try to make a bad situation work out for the good."
Because Paul's comments on slavery are part of his overall instructions in this part of his letter, which includes the instructions about wives and husbands, shouldn't all of the instructions be interpreted in the same way? Either as commands to be followed for all time and eternity, or as commands that fit the time and culture he lived in. We can't say that wives must submit to their husbands today, just as they did back in Paul's day, without also saying that slaves should be obedient to their masters today. Just my .02 on the matter.