# better than a slave
"more valuable than a slave"
# a beloved brother
"a dear brother" or "a precious brother in Christ"
# much more so to you
"he means even more to you"
# in both the flesh
"both as a man." Paul is referring to Onesimus' being a trustworthy servant.
# in the Lord
"as a brother in the Lord" or "because he belongs to the Lord"