Gal 5:1 For freedom Christ has set us free; stand firm therefore, and do not submit again to a yoke of slavery.
What 'yoke of slavery' is Paul referring to? How would his Galatian listeners understand by this 'yoke of slavery'?
Look at the preceding verses. verses 31 and 30 of chapter 4 has references to slavery. Paul is contrasting between 'children of the slave', and 'the son of the free woman'. Who is Paul referring to? He is referring to Abraham's child, the 'son of the free woman', Sarah, and contrasting Isaac, the 'son of the free woman', with Hagar's 'son of the slave, 'born according to the flesh'.
From this contrast between Hagar's child, and Sarah's, Paul uses this allegory, as an illustration of 'two covenants'; 'the one from the mount Sinai', which Paul himself, under the inspiration of the Holy Spirit, relates to bondage. And so as not to confuse anyone, and especially to befuddle his Jewish circumcision keepers of the law opponents, he identifies Sinai to bondage, and Hagar. And from this pairing of identities of Sinai, to Hagar, and to 'children of slavery', he further adds another identity marker, that is, present-day, physical and geographical Jerusalem.
So, the son of the slave, is the son, or the child born according to the flesh, and identified with Hagar, who bears children for slavery, and this slavery corresponds to Sinai, where the law was given, to condemn fleshly efforts to be in right-standing before God (justification), and this condemned flesh of slavery is further likened to physical and geographical Jerusalem.
Paul then contrasts 'present Jerusalem' which is in 'bondage' together with her children, with the 'Jerusalem which is above is free, which is the mother of us all' (v 26). We, like Isaac, are 'children of promise'. As verse 6 says, 'And because you are sons, God has sent the Spirit of His Son into our hearts, crying, "Abba! Father!" Verse 7 must be in our very DNA, spiritual man DNA that is, "So you are no longer a slave, but a son, and if a son, then an heir through God.'
An heir of God has access to all the resources of God's kingdom. And therefore, Scripturally speaking, there is absolutely no reason, or excuse to sin, or to rebel against God!
Freedom in Christ, is freedom to be His slave; a slave of righteousness. An amazingly joyful slavery to a most benevolent Master! What more could I ask for? To be His slave is my reason for living. When I am His slave, I do not have to have to be a slave to my flesh.
So, in Romans 6:1, Paul asks rhetorically, 'What shall we say then? Shall we continue in sin, that grace may abound?' Paul here is addressing the direction of grace. Prior to the experience of grace in a human heart dead because of trespasses and sin, even though sin in and around that human heart was abounding, grace was abounding even more. However, once grace comes, and makes room for Christ in the heart of one once dead in trespasses and sin, one who was taken captive by satan to do satan's will, through the desires of the flesh and the mind, grace includes in God's great big gift of salvation, union with Christ, not only in His death, when our body of sin died with Christ's human body on the cross; in addition, in union with Christ, we are made new creation in union with Christ, and we rise in newness of life, through the power of the Christ's Spirit given to us, birthing faith to be united with Christ forevermore.
And so Paul, in Romans 6, reminds the believers in Rome, 'Don't you know, as many as were baptized into Jesus Christ were baptized into His death?'
Therefore, we are buried (sunthapto - in company with, to assimilate spiritually) with Him, Jesus, by baptism into death: that like as Christ was raised up from the dead by the glory of the Father, even so we also should walk in newness of life. We should because in union with Christ, who is now raised, resurrected by the glory of the Father - the Holy Spirit - we too, in union with Christ, are also, by the glory of the Father, the Holy Spirit, enabled and empowered to walk in newness of life.
How amazing!