en_tn/gal/05/03.md

testify

"declare" or "serve as a witness"

to every man who is circumcised

"to every person who has become a Jew." Paul is using circumcision as a mmetonym for being Jewish. (See: rc://en/ta/man/translate/figs-metonymy)

obliged

"bound" or "constrained" or "enslaved"

to do

"to obey"

You are alienated from Christ

"You have ended your relationship with Christ"

seek to be justified by the law

"look for ways to have God declare you good by obeying the law." The law is metonymy for Judaism.

you have fallen away from grace

Paul is comparing a person who decides that he does not need or want the grace of Christ to someone who falls from a good high place to a bad lower place. (See: rc://en/ta/man/translate/figs-metaphor)