In Galatians 5:14, Paul alludes to Leviticus 19:18: the Law is fulfilled in one commandment, “Love your neighbor as yourself.” This verse is the most quoted verse from the Pentateuch in the New Testament, despite the fact that it is almost never referred to in contemporary Jewish texts. Perhaps this is because Jesus himself stressed love of neighbor as a fulfillment of the law!
But what does Paul mean when he says that the whole Law is fulfilled in a single commandment?
The verb “fulfill” (πληρόω) in verse 14 is a perfect passive, indicating that the completion of the Law has already been accomplished when believer “loves his neighbor as yourself.” Paul’s point is that if one is loving one’s neighbor as themselves, then they are already doing the “spirit of the Law.” By walking in the Spirit the believer is already fulfilling the whole law, but the requirements of the Law were never required for the Gentile believer in Christ (Witherington, Galatians, 381).
There was a lively debate in the first century on how to sum up the Law. Micah 6:8 might be an early example of summarizing the Law into a few principles, and the great rabbi Hillel summarized the law by saying “What is hateful to thee, do not unto thy fellow man: this is the whole Law; the rest is mere commentary.” This is not far from what Jesus says when he is asked about the greatest commandment (Matt 22:34-40). There Jesus says that the Law and prophets “hang” on these two commandments, perhaps “hinge upon” is another way of translating the verb.
Defining who is one’s neighbor was also a point of discussion, especially in the Good Samaritan parable. Jesus is asked by an expert in the Law to define “neighbor.” The lawyer likely understood the word to refer to fellow Jews, since that is what it means in Leviticus. Jesus expands this to include anyone who is in need. It is possible Paul has fellow-Christians in mind in Galatians 5:14, since the context is factions within the church (5:15, 26). A few verses later Paul expands on what he means by doing of good, in 6:10 he says that the believer in Christ ought to do good for everyone, but especially the “household of faith.”
Paul’s point is not, “if you want to keep the law, love your neighbor.” He has said repeatedly that the age of the Law is done and over with and the one who is in Christ is free from the Mosaic Law. Likewise, Paul would not agree that the believer must do good in order to “stay right with God.” The problem for Paul is “Why should a believer do good if it does not make them saved nor keep them saved?”
The question of why a believer should do good if it does not make them saved or keep them saved is a challenge. It seems to be aligned with the tension of doing good works, since we are not saved by what we do. The important thing to remember is that when we are saved, we are called to walk by the Spirit. So although loving our neighbor, doing good works and following the commandments does not make us saved, knowing that we are called to live by the Spirit compels us to want to do these things. Reeves explains this by quoting Romans 6:17-22, that slavery to God meant freedom from the enslaving powers of the law, sin and flesh (Reeves, 87). When one is filled with the spirit, life is created and the glory of the spirit is transformation (2 Corinthians 3:7-18, Reeves 83). The one law, love your neighbor as yourself, has been fulfilled by Christ completely because he is the ultimate example of love. It then should be in the believer’s desire to follow in Christ’s example and do the same.
Paul does stress freedom in Christ over works. He wanted to make sure that his converts did not cling to the law for salvation like many of the Jews of his time, but instead cling to Christ who truly gives salvation. He wanted them to know that they were free in Christ and to live by the spirit He sent. When we truly live the spirit filled life, then works flow out of us. When we live by the spirit we want to live like Jesus and live in Love like he did. As reeves puts it on page 84 “He (Paul) learned how to sacrifice personal convictions for the welfare of the group…..This was living according to what Paul called the ‘Law of Christ’, sacrificing yourself for the good of others. To ‘become all things to all people’. to ‘save some’ is to follow the pattern of Christ”.When we are living by love and sacrifice, living life by the spirit, then works are coming from our life. We are saved because we believe in Christ, and our good works come from living by the spirit. Paul urges us to “Work our our salvation with fear and trembling” in Philippians 2:12 and a very detailed description of living like Christ precedes it, So no, Good works are not required for salvation, but they come from a spirit filled life.
I think that there are a lot of reasons that we should strive to fallow the law even though our salvation is not based on works. When Paul talks about doing these things as in love your neighbor, it is not just to fallow the law but because this is what Jesus demonstrated to us to do for others. It is impotent to fallow these things because it draws our relationship closer to God and with trying to be more like Jesus as he demonstrated what our lives should look like should make us want to follow even though we are not under the Law.