In Week #3, Kay Arthur continues to prepare us for the study of the actual Sermon on the Mount by examining the true condition of the heart. According to Arthur, “men and women persist in believing that they can instill the moral, ethical structure of Jesus’ teaching without installing Jesus as their King.” (p. 46) She uses Gandhi as an example of a man who, albeit an incredible and principled leader who exemplified the teachings of Jesus, never (at least openly) accepted Jesus Christ as his savior. His heart was full of peace and love but he did not openly choose to bow his knee to confess Jesus as Lord.
What does Scripture tell us about the true condition of the heart? Genesis 8:21 tells us that “man’s heart is evil from his youth” and Jeremiah 17:9 reminds us that “the heart is more deceitful than all else and is desperately sick.” God gave the Law to Israel to make their sin and the true conditions of their hearts evident to them. In the Law God also provided the guidance and instructions for sacrifices that would atone for sin until the coming of the True Sacrifice, Jesus Christ. In Romans 7:24, Paul reminds us that the Law is spiritual and good but it is impossible for a person in the flesh to keep the Law perfectly, which leads him to ask “Who will set me free?”
We are slaves to sin and only God can set us free. How does this happen? The process is described in Romans 6:1-7 (note the process outlined in the italicized verbs that follow): those who are baptized into Christ Jesus are first baptized into His death, then buried with Him into death, then raised with Him from the dead through the glory of the Father, then united with Him in the likeness of His death and also in the likeness of His resurrection, and finally freed from sin because our old self was crucified with Him. The Christ who has died and been resurrected has freed us from slavery to sin! We now walk in the newness of life.
As believers in Christ, our hearts are no longer bound to the old covenant of the Law. We are part of the new covenant that God promised as far back as the prophet Jeremiah: “But this is the covenant which I will make with the house of Israel after those days,” declares the LORD, “I will put My law within them, and on their heart I will write it; and I will be their God, and they shall by My people.” (Jer 31:33) This covenant is no longer written on tablets of stone but on the tablets of our hearts renewed by the sacrificial blood of Christ.
It is only this kind of heart — the heart bound by the New Covenant of grace — that makes possible the kind of lifestyle described in the Sermon on the Mount.