Because of God's adoption, we aren't slaves anymore.
Paul says we Gentiles are all heirs according to the promise. Even though the Jews had this rich heritage, they still could not realize the fullness of their inheritance until Jesus came. And so they had the law that they were subject to as well. They were actually living like slaves. They had an inheritance waiting for them, but it could not be fully realized until Jesus came as Messiah.
So he's saying, Gentiles, you have the same inheritance they had. They didn't get a head start on you. Nobody got anything until Jesus came on the scene. You are adopted as his sons and daughters. Now, my two children, my beautiful kids, they are adopted. And that has been the biggest blessing in my life. I think about all of the things that we went through to qualify and be able to adopt them. And even though they will never share our DNA, there's not anything they can ever do that will not make them be an Edwards. They will always be a part of our family. They will always be at our table. He will always be my son. She will always be my daughter. And when I think about that image, I am overcome with gratitude that God tells me I cannot undo my adoption. So Paul is trying to encourage the Galatians to not be so caught up and distracted by what the Jews say they're bringing to the table.
He says, at the end of the day, it didn't matter if you had generations of legacy behind you or you came to know Jesus today, nobody could get the fullness of what God promised until Jesus came on the scene. So they had a guaranteed inheritance, but he says it was under the control of another. It was waiting for this appointed time. There was this temporary thing that the Jews had until Jesus could come and fulfill the entire law. So Paul is encouraging the Galatians and reminding them yet again that even though the Jews had generations of religion and law and ceremony that they had been subject to that nobody really realized the inheritance until Jesus came on the scene. He says they were like children and they were no different from slaves. It's like if you are a child and at age 18 your parents or maybe a distant relative has some inheritance waiting for you. From zero to 18 you may have the inheritance waiting, but you can't really live in that inheritance because it's under the guardianship of someone else.
Jesus is the person that allows us to realize the fullness of our adoption. So Paul says, don't live like you don't already have your inheritance. A child that has an inheritance waiting for them, well, they don't have to be fully responsible. Someone else is managing the money, managing the resources. They can do whatever they want to do because they're not ultimately responsible, but a day is going to come when the inheritance is going to be handed to them and it would be unwise for them to continue to act like an eight-year-old after they've realized their inheritance. Paul is saying, you have everything that you need in Christ Jesus. Why would you choose to live immaturely when God has given you the fullness of your inheritance? How many times as adults do we still act like children when God is saying, you have everything you need, you don't have to throw a temper tantrum. You don't have to complain about what God hasn't given you, what someone else has in comparison. You have it all, and Paul is driving this point home because if we don't think we have it all, then we'll still be looking for it in lesser sources.
We will believe what someone else says. We will seek approval, seek affirmation from places that can never give what Jesus has already given us. So what elementary principles might we still be enslaved to? Paul is talking about simple things. They really should not occupy our minds as much as they do. Is it money? Is it that your whole life you said, I just don't want to be poor? I want to make a certain income. Is it a career? Is it some promotion that you want? Is it attaining that certain degree? Is it the family that you've always wanted? Those things are important, but they are minor things compared to the inheritance that we have in Jesus. Paul says, if we are living like we don't have the inheritance that Jesus has given us, it's like an adult that still has to be told when to go to bed.