“Blessed are the poor in spirit, for theirs is the kingdom of heaven.” So Jesus began his Sermon on the Mount, from which our Gospel is taken. The “poor in spirit” are those who have been brought to the realization—something they never would have concluded on their own—that they have nothing to offer God that can contribute in any way to their salvation. Because of this, they mourn, are meek rather than arrogant, and hunger and thirst for righteousness. They are also reviled and persecuted by a world that hates the Christ they embrace for salvation and life. That doesn’t sound as if they are blessed at all, does it? And yet our Lord, in this sermon, tells them to rejoice and be glad, for theirs is the kingdom of heaven.

Not surprisingly, sinful man sees things quite differently. Rather than seeing poverty, mourning, meekness, hunger, thirst, and persecution as blessings, he regards them as signs of weakness and being cursed. By nature, he is proud, strong, and self-assured. Rather than glorying in God’s grace, he glories in his own abilities and accomplishments. This explains why so many church bodies falsely teach, and why so many Christians are so easily misled into believing, that Jesus preached this sermon to instruct his disciples on what they must do to prove themselves righteous enough to enter the kingdom of heaven.

It is true, of course, that only the righteous will enter this kingdom. But the righteousness God requires surpasses the abilities of fallen men. Jesus made this crystal clear in his Sermon on the Mount when he told his disciples, “For I say to you, that unless your righteousness exceeds the righteousness of the scribes and Pharisees, you will by no means enter the kingdom of heaven.”

The Pharisees in Jesus’ day, along with the group of scribes within their sect, were considered the most outwardly righteous among the Jews. They devoted their lives to walking the walk and talking the talk. Yet even their righteousness, Jesus says, was not enough. For the righteousness God requires is a perfect righteousness. Jesus’ interpretation of the Fifth Commandment in this sermon reveals just how impossible it is for sinful men—including you and me—to obtain such righteousness.

“You shall not murder.” That’s what the Fifth Commandment declares. But simply refraining from murder does not qualify as keeping it. I’ve never murdered anyone, and yet I have in no way fulfilled what God demands—not even close. Listen to how far Jesus takes this commandment: “Whoever is angry with his brother without a cause shall be in danger of the judgment,” and he who speaks a word of condemnation against him is in danger of hellfire.

From this, we see that in God’s eyes, murder is not only an outward act but also an inward one. It involves not just taking someone’s life unjustly, but also harboring hate rather than love in one’s heart toward that person—regardless of what they may have done or said.

Now that you’ve heard just how far the law reaches—that it touches not only your deeds and words but also your emotions and feelings—do you really think Jesus preached this sermon to instruct his disciples on what they must do to enter the kingdom of heaven? From this one commandment alone, he shows you that you do not possess the righteousness that merits eternal life. What you truly deserve is for him, the Judge, to hand you over to the officer, Satan, who would then throw you into the prison of hell.

But in his great mercy for you, God’s Son endured those searing flames in the hellish heat of Golgotha. He paid for your sins with his life. He suffered the death that was the due penalty for your sins, and in doing so, he won for you God’s forgiveness—freedom from the eternal prison sentence your sinful thoughts, words, and deeds had earned.

So that the salvation he won might be given to you personally, he instituted Holy Baptism. “Or do you not know that as many of us as were baptized into Christ Jesus were baptized into his death? Therefore we were buried with him through baptism into death, that just as Christ was raised from the dead by the glory of the Father, even so we also should walk in newness of life.”

In the simple act of Holy Baptism, Christ’s work of redemption was credited to you: his death became the death that paid the punishment for your sins; his burial, the burial that removed your sinful flesh from God’s sight; and his resurrection, the resurrection that made it possible for you to be raised to a new life as a forgiven child of God.

While you have been set free from the prison of hell through your baptism into Christ, the question remains: are you righteous enough to enter the kingdom of heaven? Yes—by all means—but not on the basis of your own righteousness. It is the righteousness of Christ, who perfectly kept not only the Fifth Commandment but every one of God’s holy, immutable decrees in your place. His righteousness is what makes you worthy to enter the eternal kingdom. And it was imputed to you—made your own—also in your baptism: “For as many of you as were baptized into Christ have clothed yourselves with Christ,” as the blessed Apostle explains.

From this, you can see the true purpose of Jesus’ Sermon on the Mount. Rather than instructing you on what you must do as disciples of Christ, it describes who you are through faith in Christ. You are righteous—far more righteous than the scribes and Pharisees—for yours is the perfect righteousness of Christ himself.

Therefore rejoice, dear Christian, and be glad. The kingdom of heaven is opened to you. And so that it remains open to you—even unto death—your Lord will now satisfy your hunger and thirst for righteousness by serving you his Body to eat and his Blood to drink for the forgiveness of your sins, thus assuring you of everlasting life and salvation.

In the Name of the Father, and of the Son, and of the Holy Spirit. Amen.