If you really fulfill [the] royal law according to the Scripture, [ “You shall love your neighbor as yourself,”] you do well; James 2:8 (NKJV)
The royal law is not the laws of men or nature, it’s not the law of Moses also known as the ten commandments.
The royal law is the law of our Lord and King, Jesus Christ the King of Kings and Lord of lords.
It is the law of Love. It is the law of loving others even as our Lord and King has loved us. John 15:12 (NKJV) This is My commandment, that you love one another as I have loved you. The law of love believes about others what Jesus believes about us. Love believes the best of others. It is doing to others as Jesus has done to us. He laid down His life for us. He did not, He doesn’t and He will never hold our sins and offenses and shortcomings against us. It is seeing others, treating others as Jesus has done to us. John 13:15 (NKJV) For I have given you an example, that you should do as I have done to you. He sees and treats us as valuable and worthy. It is sharing all we are and have with others just exactly like Jesus did and continues to do.