"he (Paul) feels he has the right to command Philemon to free Onesimus,"
From your own quote above, ... clearly Paul is against slavery.
HE DIDN'T, THOUGH!
And Paul says:
"All under the yoke of slavery must regard their masters as worthy of full respect...Those slaves whose masters are brothers in the faith must not take liberties with them on that account. they must perform their tasks even more faithfully, since those who will profit from their work are believers and beloved brothers." 1 Timothy 6:1ff
"To slaves I say, obey your human masters perfectly, not with the purpose of attracting attention and pleasing men, but in all sincerity and our of reverence for the Lord." Colossians 3:22
"You slave owners, deal justly and fairly with your slaves..." Colossians 4:1
"Slaves are to be submissive to their masters. They should try to please them in every way, not contradicting them nor stealing from them, but expressing a constant fidelity by their conduct, so as to adorn in every way possible the doctrine of God our Savior." Titus 2:9
"The general rule is that each one should lead the life the Lord has assigned him, continuing as he was when the Lord called him...Were you a slave when your call came? Give it no thought. Even supposing you could go free, you would be better off making the most of your slavery...." 1 Corinthians 7:17ff
Nowhere does he even hint: "Stop with the goddam slavery...it is wrong." If he actually was "clearly against slavery"...HE WOULD HAVE SAID SO.
Paul's god says there is nothing wrong with owning and selling slaves.
Stop with the nonsense here, Dog.