All these major themes of slavery, freedom and the liberating work of Christ are now summed up in the ringing affirmation of 5:1: It is for freedom that Christ has set us free.

That indicative is followed by an imperative, Stand firm, then. This may sound like a dull lesson in grammar, but it is actually central in Pauline ethics. What we must do (the imperative) is always based upon what God has already done (the indicative). Or to put it another way, what God has done gives us the opportunity and power to do what we must do. This indicative-imperative structure is seen here in verse 1 and also in verses 13 and 25. So it provides the structure for the whole chapter: God's gift of freedom must be defended (v. 1); God's gift of freedom must not be abused but must be used to serve (v. 13); God's gift of life by the Spirit must be expressed through the Spirit (v. 25).

In Paul's letters he often exhorts his readers to stand firm: "stand firm in the faith" (1 Cor 16:13); "stand firm in one spirit" (Phil 1:27); "stand firm in the Lord" (Phil 4:1). Here he appeals to them to stand firm in the freedom Christ has given to them. Paul illustrated in his autobiography how he stood firm in his freedom against "false brothers" who "infiltrated our ranks to spy on the freedom we have in Christ Jesus and to make us slaves" (2:4). He did not give in to their pressure to make Titus, a Gentile convert, a Jew by circumcision. Now similar false teachers have infiltrated the ranks of the Galatian churches with the same demand. They have been putting the Galatian converts under intense social pressure to become Jews by being circumcised. Stand firm, Paul says. Do let yourselves be burdened again by a yoke of slavery (v. 1).

In Paul's day one could often see oxen harnessed by a yoke to a heavily laden cart, straining to pull their burden uphill while being goaded with sharp sticks. Paul uses the word yoke, as it was often used by his contemporaries, to refer to the yoke of the law. We can see from his statement in verse 3 that the crushing weight of this yoke is the obligation to obey the whole law. A similar use of yoke can be seen in Peter's speech at the Jerusalem council, as reported in Acts 15:10: "Why do you try to test God by putting on the necks of the [Gentile] disciples a yoke that neither we nor our fathers have been able to bear?" The yoke of the law is a yoke of slavery, because it places us under the burden of commandments we cannot keep and under curses that we deserve for our disobedience. But God sent his Son to lift this heavy yoke from our shoulders and to take it upon himself: he was "born under law" (4:4) and kept all its demands for us; he died under the curse of the law for us (3:13). Since he has set us free from this yoke of slavery, we must not take it on ourselves again. In contrast to the yoke of slavery under the law, his yoke is easy and his burden is light (Mt 11:30).

In order to strengthen his readers' resolve to defend their freedom in Christ and resist the false teachers' efforts to put them under the yoke of slavery to the law, Paul sets forth the terrible negative consequences of submitting to this yoke of slavery in verses 2-4. Then in contrast to this negative picture, he sets out a positive description of maintaining our freedom in Christ in verses 5-6.