Jesus came to the earth to address and deal with the root issue of sin, corruption, and the overall human condition. Within this work, He reconciled the relationship between God and creation. He became the first of the new type of human that creation is so desperately in need of, the type of human that embodies the new creation, the image of God, and the philosophy of His kingdom. In the following series of topics, Jesus illustrates what true righteousness is and shows us that it is not only what we do but why we do it that determines our righteousness.
First of all, it is essential to note that in Jesus’s repeated use of the phrase, but I say to you throughout these sections, He clarifies that He is the Son of God and the author and giver of the law. This statement is one of total divine authority.
It is made clear in the Old Testament and the law of the Torah that we are not to murder each other; this is found in Exodus 20:13. However, Jesus targets the root cause of this issue, anger, as anger is the inner intention and emotion leading to murder. Jesus says that even if we are angry with our brother or sister (brother or sister in this context going well beyond a fellow Christian as a follower of Jesus has no limits as to who their brother or sister is), we have just as much as murdered them. Jesus is not concerned with the outward appearance of things; He is concerned with the root condition of the heart. He knows that if the root of our hearts is corrupt, the outward appearance is corrupt and can be manipulated to appear as if it is pure. However, if the root of our hearts is pure, we can only outwardly show that purity and righteousness. The heart is the source from which all things come, which is why He identifies our hearts as the place where He lives within us. When Jesus lives and reigns in our hearts, everything that comes out of us looks like Him. The heart is the birthing place of who we are; it is the source of our character. This first law that Jesus addresses is the one that entrusts the well-being of others to our care, showing us that to follow Him is to prioritize the well-being of others.
Jesus details three progressions of this anger in the heart that leads to murder. The first is the unexpressed feeling of anger towards another person. This emotion makes its way outward in the casual word raca, a simple expression of anger that is not explicit. The next progression comes in the form of a deliberate insult and degradation of another person in the expression you fool! It is then imagined that the next series of events become physical and ultimately lead to murder, in which one takes the sacredness of life into their own hands, unrightfully taking the exclusive role of God. Jesus shows us how a seemingly meaningless feeling can evolve quickly into a destructive force. This is why He has come to deal with these issues at their fundamental level. As the followers of Jesus, we must be pure in heart and intention. We can do so by allowing Jesus to rule within our hearts and being led not by way of emotion or what happens to us but by the Spirit of God within us.
After making the connection between the act of murder and the feeling of hatred within the heart, Jesus then emphasizes the seriousness of this issue by referring to someone who would attempt to offer sacrifices to God without first being in right standing with others, even within their hearts. Righteousness is not just right standing with God or right standing with others; it is both of them combined; they are interdependent. God will not be separated from the well-being of others, and to Jesus, the service of God and the service of others, even the least of them, were understood as one. This is exactly what Jesus is communicating when He summarizes the law and the prophets by saying, love God and love others, they are the same commandment. The performance of an act of worship does not negate our duties and responsibilities towards others. Jesus says before we bring anything before God, go and make it right with those who we are in conflict with. We see David echo this idea in Psalm 51. God desires the heart and sacrifices to Him are meaningless without it.
The law and the love of Christ, which are synonymous, look past the external and go right for the heart, which is the source of all action and our overall character. The law and the love of Christ seek to preserve, support, and protect life. The Sermon on the Mount is, to a great extent, a response to the misunderstanding of the law and what it means to be God’s people. In giving His interpretation of the law and the righteousness that follows upon its observance, Jesus shows us that they go well beyond the external act of obedience and find their home in the purpose of the heart. The danger revealed is that in focusing on the external act of obedience, the heart's motives may be ignored entirely, and while we may look righteous, our hearts speak otherwise.