Sermon on the Mount (09): Righteousness and the Law
In Matthew 5:17–20, Jesus declares that He has not come to abolish the Law or the Prophets but to fulfill them. This is one of the most important statements in His Sermon on the Mount. Many in His audience would have been shocked. The scribes and Pharisees had elevated the Law, often twisting it into something rigid, external, and manageable. Jesus, however, restores the Law to its full meaning—one that reaches into the heart, not just the hands.
The Pharisees had created a form of righteousness that was more about appearances than truth. They emphasized rules and traditions, but they often missed the point of God’s original intent. They reduced God’s commandments to something they could perform in public while avoiding inward transformation. Jesus exposes this shallow version of righteousness and invites us into something far deeper and more difficult—but also more beautiful and true.
Jesus fulfilled the Law perfectly. He obeyed every command of God without sin, and He brought clarity to the true meaning behind each part of the Law. He lived in such a way that every promise, prophecy, and standard of righteousness found its fulfillment in Him. He didn’t reject the Law; He completed it.
When Jesus says our righteousness must exceed that of the scribes and Pharisees, He isn’t saying we need to follow more rules. He is pointing us to a different kind of righteousness—one that starts with inner transformation and results in outward obedience. This kind of life is only possible through the Spirit of God living in us.
Jesus uses the phrase, “You have heard that it was said… but I say to you…” multiple times in Matthew 5. He is not canceling the Old Testament commandments. Rather, He is correcting the ways people had misinterpreted them. These statements show the deep intent of the Law. For instance, the commandment against murder isn’t just about not killing someone. It’s about the anger, contempt, and bitterness in the heart that lead to broken relationships.
This emphasis on the inner life continues throughout the Sermon. Jesus shows that sin begins in the heart—whether it’s lust, hate, pride, or greed. The Law points to God’s standard, but only grace and the Spirit make it possible for us to grow in that direction.
Under the new covenant, as prophesied in Jeremiah 31 and Ezekiel 36, God writes His Law on our hearts and gives us His Spirit to empower us. That’s the only way we can live out the kind of righteousness Jesus describes. The Law was never meant to be reduced to checklists. It was meant to guide us into a life aligned with God’s character.
The Pharisees were skilled at manipulating the Law to suit their own interests. They created loopholes and focused on what people could see. For example, they debated how far one could walk on the Sabbath without “breaking” it, yet they missed the Sabbath’s true purpose—rest and worship. They were more concerned with technical obedience than with truth or love.
Jesus makes clear that God cares more about who we are becoming than just what we are doing. He wants truth in the inner parts (Psalm 51:6). Jesus warns that those who set aside even the least of God’s commands will be called least in the kingdom. But those who obey and teach them will be called great. This is not about earning favor through performance. It is about honoring God from the heart.
The kind of righteousness God desires is never merely behavioral. It’s not about how we appear on Sundays or what religious words we use. It is about our hearts being shaped by grace.
Some people treat the Sermon on the Mount like a set of moral goals for everyone. But in truth, it is a description of life in the kingdom of God. You cannot live it out apart from Christ. If you try to do so without the Spirit, it will either lead to pride or despair. You will either think you’re succeeding (and become self-righteous), or you’ll realize you’re failing (and give up in shame). Neither response leads to life.
But the message of the gospel is that Jesus fulfilled the Law for us and now lives in us through the Spirit. The Christian life isn’t about trying harder. It’s about trusting deeper. When we abide in Christ, the Spirit begins to form His character in us. We grow in humility, love, patience, and holiness—not as a performance, but as the fruit of grace.
Paul explains this well in Romans 8:3–4. He says that what the Law could not do because we were weak in the flesh, God did by sending His Son. Now, the righteous requirement of the Law can be fulfilled in us who walk by the Spirit. The Sermon on the Mount is not a standard we meet to get into the kingdom. It is a picture of what life looks like for those already in the kingdom by grace.
When Jesus talks about righteousness, He isn’t asking for more effort—He’s asking for surrender. He wants to live His life through us. True obedience isn’t a human achievement. It’s a response to God’s work within us.
God is not looking for rule followers. He is looking for people who love Him with all their heart, soul, mind, and strength. He’s calling for a whole-life transformation—where the Spirit shapes our thoughts, motives, words, and actions.
This is why Jesus tells us that our righteousness must go beyond the Pharisees. It must go beyond external conformity and flow from a heart renewed by the Spirit. God’s desire is not just to forgive our sins but to remake us into the image of His Son.
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Questions for Reflection
- In what ways have I relied on external behavior to define righteousness, rather than surrendering to the inward transformation of the Spirit?
- How do I respond when my desires begin to lead me away from God’s best?
- Am I daily seeking the Spirit’s guidance and empowerment, or am I attempting to live the Christian life by my own effort?
- When I fail, do I allow guilt to keep me from moving forward in grace, or do I return to God with a repentant heart and renewed trust in His forgiveness?
