Jesus is taking the Law and setting it forth in such a way that we get a good look at what is going on in us.
Very often, when a doctor wants to make a diagnosis, he or she has to look at your insides. We have come a long way since the days when the only way to do this was “exploratory” surgery. Today there are a variety of means at our disposal, everything from sonograms and X-rays to various CAT and MRI scans, all to deliver a picture of what is going on inside you.
“What is going on inside you.” This is what the long excerpt from Jesus’s Sermon on the Mount in Matthew 5:21-37 is all about. Jesus is taking the Law and setting it forth in such a way that we get a good look at what is going on in us. Here we are using the Law as a mirror, so:
“...whatever the Law says, it says to those who are under the Law, so that every mouth may be silenced and the whole world held accountable to God. Therefore, no one will be declared righteous in God’s sight by the works of the Law. Rather, through the Law we become conscious of our sin” (Romans 3:19-20).
The Law needs to be preached this way, so it is not merely a matter of auditors considering if they have committed this or that peccadillo, but rather the condition of their heart that only Christ, with the Holy Spirit, can remit, redeem, and renew.
Within the Sermon on the Mount, Jesus challenges the opinions of the “doctors of the law” of His day, by putting humanity into the divine MRI of the Law. It is the Law from the perspective of the Creator God, not “the traditions of the elders.” And it comes out like this:
“The heart is deceitful above all things, and desperately sick; who can understand it? ‘I the Lord search the heart and test the mind, to give every man according to his ways, according to the fruit of his deeds’” (Jeremiah 17:9-10).
From the divine perspective, there is no justification to be found in one’s heart, no appeal to a “good heart” as far as the Law is concerned. The Lord denominates man’s heart as “deceitful about all things,” “desperately sick,” and beyond the ability of any person, be it a philosopher, psychologist, or theologian, to properly diagnose: “Who can understand it?” Then comes the scary part. God scrutinizes the heart and tests the mind to levy judgment, the outcome of which stands determined because the heart is deceitful above all things (see Genesis 6:5). The Law offers no hope. And if Matthew 5:21-37 give us the blunt diagnosis, then 5:48 issues a postmortem certificate. Again, the Law offers no hope.
But the Law also purposes to drive us from an inward focus to an outward one. Indeed, leads us to faith in the One who promises grace: “So, then, the Law was our guardian [or schoolmaster] until Christ came, in order that we might be justified by faith” (Galatians 3:24).
But the Law also purposes to drive us from an inward focus to an outward one.
This exposes a basic problem with preaching the Law as merely prescriptive or proscriptive deeds. When we do, it becomes “doable” and, as such, a means of self-justification. The “traditions of the elders” tamed the Law and made it doable, predicated upon an unbiblical anthropology of human ability, such that yields a theology of self-justification. It is the same trap Satan set in Eden, “Lean on your own understanding,” but God looks on the heart. So, it persists as an irrepressible anthropology promulgating the false hope that “God looks on the heart” while we evidence the deeds (works) of our “good hearts.” It is the unqualified self-diagnosis of a patient who, though riddled with stage-four cancer, examines himself and thinks, “I feel fine.”
At the time of the Reformation, a Roman Catholic friar named Martin Luther was vexed by an Aristotelian spin on the Law. Aristotle made the distinction between something possessing potentiality, and it yielding actuality. Some Church of Rome theologians applied this distinction to our relationship to the Law, so only actual sins (sinful words and deeds) mattered to God. Ungodly thoughts, desires, and dispositions were merely concerns of “potentiality.” A person could, then, conduct their business with God through a calculus of merit: Stay away from actual sins (demerit), and do good works (merit). Luther, however, was plagued with a case of conscience concerning the dispositions of his heart. Potentiality was the powerhouse of sins. In other words, the Augustinian friar was acutely aware that Sin is nothing other than human nature, which, although its powers were broken and nullified by forgiveness and regeneration, nevertheless would abide until our death. Consequently, it required a more radical dependence on Christ and a constant resorting to a “lifetime of repentance” and faith in Jesus who alone accomplishes and applies saving grace. He alone justifies sinners.
While the Pharisees and Aristotelians address symptoms and outbreaks of the disease, Jesus, on the other hand, takes a PET scan of humanity’s internal condition. He does so by exposing not simply what is going on with our hands and our eyes, which are the things we do, but in our hearts, the human condition per se. It is noteworthy that Jesus does not employ the Enlightenment’s fashionable tripartite depiction of “mind, will, and emotions,” but the Hebrew and biblical description of the heart, where the heart means the seat of our “self,” what comprises the fundamental dispositions of being human. So, Jesus is not simply talking about the external symptoms we call “s-i-n-s” (for which He makes a propitiatory blood atonement and expiates our sins, remitting our guilt), but the internal condition with a capital “S,” Sin. It is the crisis and condition of Sin which necessitates Jesus’s representation of us, substitution for us, and redemption of us so we may have hearts reborn “from above,” becoming offspring of the Last Adam. The old Hebrew prophecies of remaking human hearts, about which Jeremiah (31:33-34) and Ezekiel (36:26-27) spoke, have their reality in the regeneration Jesus affects in the waters of Baptism (2 Corinthians 5:15-19; Ephesians 5:25-27). We are justified by His life, crucifixion, and resurrection, but we are also regenerated, given new hearts, as a result of being united to Him. Therefore, it is this new heart which makes possible Christian living according to the spirit and ethic of His Kingdom. That is the Law refashioned for its “third use.”