v8, Royal law refers to an imperial edict which became a supreme law and overwrote other laws (Ezra 6:11; Est. 8). Here, it refers to God being the Supreme King and His Law as absolute. If Jesus is Lord & King, then we are obligated to follow His decrees (Lev. 19:15-18; Deut. 6:5; Matt. 22:36-40; Rom. 13:8-10)
v9, Sin, The definition of this word is simply, “to miss the mark”. Whether we like it or not, all humans have a Creator that has given us a target, as well as an arrow. There are three ways to sin. 1, shoot and miss accidentally. 2, shoot and miss intentionally. 3, don’t shoot at all. Sin is sin, unless you hit the bullseye. God’s perfect law of liberty in Christ, the law of faith is our bullseye.
v10, Whole law. The Bible teaches that some sins are more heinous than others; however, in God’s sight, sin is sin. A small sin will condemn you just as much as a bigger one. James warns us not to have a superficial understanding of the Law (God’s Word) (Matt. 5:17-20).
v11, Adultery & Murder. (Mark 12:29-34). James is putting the abuse of the poor and favoritism as a violation of the Great Commandment, and in the same category as murder and adultery! During this time, Jewish Zealots who were too religious to commit adultery would stab the Jewish aristocrats in the Temple court. James is also saying not to go to the other extreme, either. So God’s children couldn’t think that because they kept their personal life pure, they were better than people who were publicly shameful (aristocrats) and that personal purity with God gave them the higher position to execute judgment on their own brothers. Transgressors. The Jews, classically, had a hierarchy of sins-which were the real bad ones, and which were minor. The point James is making, as did Jesus, is that when we sin, we sin; From God’s perspective, there is no “pecking order” or hierarchy (Matt. 5:18-19; 23:23).
v12, Be judged. This refers to how our words and actions reflect who we are and what is in our heart (1 John 3:18). It is amazing that Christians are expected to look upon themselves as legal convicts (transgressors) of The Law of Liberty. Jesus gives us liberty, grace, and his own spotless righteousness, even though we are not as perfect as this royal law. That is amazing. So we are expected to treat other people amazingly! Love them.
v12, Law of liberty refers to being free from the ways of the world. It can also mean being wise in our own eyes. Most scholars believe it means being freed from sin (James 1:25). However you look upon the phrase, the law of faith in Christ itself is perfect, Romans 3:27.
v13, Mercy. God is not obligated to give mercy to anyone; yet, He does so anyway, and in abundance (Zech. 7:9; Matt. 5:7; 18:21-25; Rom. 9). Judaism recognized that God’s greatest attributes are His mercy and Judgment. If we are not impartial in our judgments, it will fall back on us! We always have to remember we are given grace, liberty, and forgiveness, but never forget we also have responsibility. We are called to give mercy and forgive-as God has done with us (Matt. 18:23-35). See Ephesians 4:32.
The basic, simple, and true thought is that we are to treat others as Christ has treated us! Being a Christian means we are to see one another as who we are in Christ. We are to treat one another the way Christ has treated us, because He first loved us. Do we see each other as the children of God just as we are the child of God? (1 John 2:28-3:3). Each of us is a brother or sister in the Lord. So, we must treat one another as Christ has treated us! We do this through the empowerment of His Spirit!