The point of this passage is to communicate that the goal of following Christ is not simply to ensure your own freedom and salvation, but to extend that opportunity to everyone around us. And to not just offer the gospel message as an outsider or unfamiliar, but to go to great lengths to become like the people around us so they can understand the gospel in a familiar and comfortable context.
This concept is exactly how God was operating when Jesus came to us in the form of a human. The incomprehensible, unending, all powerful, all knowing God came to us in a form that we could understand, relate and connect to so that we could know him and the message he was carrying. He has set the ultimate example of becoming relate-able to others for the sake of providing them the opportunity to know the Gospel. If God had never taken that step toward us, then we would still be living under the old covenant of the Law. And now that we have experienced and understood the message of the Gospel, it is our responsibility to become relate-able and approachable to others so they can experience what we have received.
It is important to keep in mind two things throughout this mission of becoming relate-able to others. First, in vs. 20, Paul explicitly states that, though he becomes like those under the Law to reach them, he is not bound under the law. It is important to remember that you live in the freedom and fullness of life that Jesus provides for us, that the Law could never give us. And second, in vs. 21, Paul states that, while he becomes like those outside of the law, he does not forsake the life of freedom under the law of Christ. It is important that as we try to relate to others who do not know Jesus, we do not stray from seeking to honor God in everything we think and do and pursuing Christ-likeness. Given those two things, I would encourage you to think of people in your life who don't know who Jesus is. How can you become relate-able to them? How can you become approachable, for the purpose of revealing the goodness of Christ through the Gospel?
My prayer would be that we would be willing to become whatever we need to in order that as many people as possible could be provided the opportunity to encounter God and understand the life and freedom He is wanting to lead them into.
- Will Goodwin