Paul Bragged That He Was A Slave Of Christ Jesus

Most folks brag about their achievements. “I’m the president of the chamber of commerce” they might say. “I’m a lawyer with Smith and Dugall.” they might say.
But Paul says he’s a “slave” of Christ Jesus.
What’s going on here?
Doesn’t he know that slavery is soooooo wrong?
Well, apparently, Paul’s understanding of slavery and the modern American mindset about slavery are two different things.
Long, long ago, slavery could be a “step up”… if, say, you were deeply in debt, and you sold yourself into slavery to cover the debt.
Plus, the slave owner had an obligation to take care of his slave.
This opening line in Romans chapter one… is unlike anything we’d ever hear from modern day preachers like Joel Osteen. Or “freewill” bible teachers, who don’t believe in the sovereignty of God. Freewillers believe in man’s so-called “freewill” and can’t imagine anything like Romans chapter 9… much less BRAGGING that you’re a SLAVE OF CHRIST JESUS.
Leave me your comments about this statement by Paul.
I’m just trying to sort it out in my head. What’s going on here?

Paul… a slave of Christ Jesus… if we follow this idea, that, Paul was devoted to Christ, but Christ as his owner, was devoted to Paul as well.