God's Autograph: The Law and the Spirit Text: Exodus 31:18
Introduction: The Unavoidable Lawgiver
We live in an age that is desperate to have law without a lawgiver, morality without a transcendent source, and justice without a judge. Our secularist priests want to build a society on the shifting sands of human opinion, popular consensus, and whatever the Supreme Court decided last Tuesday. They want the fruit of righteousness, things like human rights and dignity, without the root of righteousness, which is the character of the living God. But this is like wanting to have cut flowers without the nuisance of a garden, soil, and water. It is a doomed project, and the flowers are already wilting.
Every society is a theocracy. This is not a question of whether, but which. Every legal system is the codification of a particular morality, and every morality is grounded in a particular theology, a particular view of ultimate reality. The question is not whether we will have a god over our society, but which god it will be. Will it be the triune God of Scripture, or will it be the bloated, bureaucratic, and bloodthirsty god of the state? Will it be Yahweh, or will it be Caesar, or Moloch, or Mammon?
When modern man hears about the law of God being given at Sinai, he instinctively recoils. He pictures a grim-faced deity imposing arbitrary rules on a cowering populace. He thinks of oppression, restriction, and the death of freedom. But this is because he has been catechized by the enemies of God. He has forgotten, or has never known, the preamble to the Ten Commandments. God does not begin with "Thou shalt not." He begins by announcing His great act of liberation: "I am the LORD your God, who brought you out of the land of Egypt, out of the house of slavery" (Exodus 20:2). The law is not given to a people in order to enslave them; the law is given to a people who have already been set free, in order to teach them how to live as free men. It is the constitution of liberty.
The verse before us today is the capstone of this entire glorious, terrifying encounter between God and His people on Mount Sinai. It is the moment of divine certification. It is God putting His signature on His covenant constitution. And in this one verse, we find the foundation of all true authority, the nature of God's personal interaction with His world, and a profound pointer to the work of the new covenant in the hearts of His people.
The Text
When He had finished speaking with him upon Mount Sinai, He gave Moses the two tablets of the testimony, tablets of stone, written by the finger of God.
(Exodus 31:18 LSB)
God's Conversation and God's Conclusion
The verse begins with a simple but profound statement: "When He had finished speaking with him upon Mount Sinai." This was not an impersonal transaction. This was not a memo sent down from the celestial corporate headquarters. This was the culmination of a forty-day conversation between God and Moses. God is a speaking God. He is a relational God. The foundation of our universe is not silent, impersonal matter, but rather the Father, Son, and Holy Spirit in eternal, loving communion. The Word was with God and the Word was God. Communication is at the heart of reality.
For forty days and forty nights, God had been speaking with Moses, giving him the intricate details for the tabernacle, the priesthood, and the sacrificial system. All of it was a glorious architectural blueprint of the gospel. All of it pointed forward to the person and work of Jesus Christ. And now, that conversation concludes. God has said what He needed to say for this stage of His covenant plan. The speaking is finished, and the giving begins. This is always God's pattern. First the Word, then the tangible sign. First the declaration, then the sacrament. He speaks creation into existence, and then He rests. He preaches the gospel, and then He gives baptism and the supper.
What He gives Moses is "the two tablets of the testimony." The law is a testimony. It is a witness. What does it witness to? It witnesses to the character of God. The law is a transcript of God's own holiness, righteousness, and goodness. It tells us what God is like. He is faithful (one wife), He values life (do not murder), He is the owner of all things (do not steal), and He is true (do not bear false witness). To break the law is not just to break an arbitrary rule; it is to assault the very character of God. This is why sin is so serious. It is a personal affront to our Creator.
And notice there are two tablets. This has traditionally been understood to represent the two great divisions of the law: our duty to God (commandments 1-4) and our duty to our neighbor (commandments 5-10). You cannot have one without the other. You cannot claim to love God whom you have not seen if you hate your brother whom you have seen. And you cannot truly love your neighbor as yourself if you do not first love the God in whose image both you and your neighbor are made. Vertical fidelity is the only possible foundation for horizontal stability.
Written in Stone, Written by God
Next, we are told the nature of these tablets. They are "tablets of stone." This is significant. Stone signifies permanence, durability, and unchangeable authority. God's moral law is not a suggestion. It is not a set of cultural preferences that evolve over time. It is as fixed and unchanging as the God who wrote it. Jesus Himself said, "For assuredly, I say to you, till heaven and earth pass away, one jot or one tittle will by no means pass from the law till all is fulfilled" (Matthew 5:18). Our modern world wants a god made of putty, a law written in disappearing ink. But the God of Sinai writes His law in stone.
But the most startling detail is the last one. These tablets were "written by the finger of God." This is a stunning anthropomorphism. God is spirit; He does not have physical fingers. This is biblical language to convey a direct, personal, and powerful action of God Himself. This was not delegated. God did not dictate the law to an angelic secretary. He wrote it Himself. This is God's autograph. The authority of this law is absolute because its author is the absolute sovereign of the universe.
The phrase "finger of God" appears elsewhere in Scripture, and it is immensely instructive. When the Egyptian magicians saw a plague they could not replicate, they confessed, "This is the finger of God" (Exodus 8:19). It signifies a work of undeniable divine power. But most importantly, Jesus uses this exact phrase in the New Testament. When the Pharisees accused Him of casting out demons by the power of Satan, Jesus replied, "But if I cast out demons by the finger of God, then the kingdom of God has come upon you" (Luke 11:20). In Matthew's parallel account, he records Jesus as saying, "by the Spirit of God" (Matthew 12:28).
Here is the interpretive key that unlocks everything. The finger of God is the Spirit of God. It was the Holy Spirit who carved the Ten Commandments into the tablets of stone on Mount Sinai. The third person of the Trinity was the author of the external law. This is crucial. The law is not at odds with the Spirit. The Spirit is the one who wrote the law.
From Stone to Heart: The New Covenant
So why does the Apostle Paul say that "the letter kills, but the Spirit gives life" (2 Corinthians 3:6)? Is he contradicting what we have just established? Not at all. He is explaining the difference in the location of the law. The problem in the old covenant was not with the law itself. The law is holy, just, and good (Romans 7:12). The problem was with the people. The problem was that the law, written by the Spirit on tablets of stone, was external to the sinner. It stood outside of man, testifying against his sin and condemning him. And because man's heart was made of stone, he could not obey it. A law written on stone confronting a heart of stone can only produce condemnation and death. The letter, when it is only an external letter, kills.
But God promised a solution to this problem, a new covenant. Through the prophet Jeremiah, He said, "I will put My law within them, and on their heart I will write it" (Jeremiah 31:33). Through Ezekiel, He promised, "I will give you a new heart and put a new spirit within you; and I will remove the heart of stone from your flesh and give you a heart of flesh" (Ezekiel 36:26).
This is precisely what Paul is talking about in 2 Corinthians. He tells the Corinthian believers that they are an epistle of Christ, "written not with ink but by the Spirit of the living God, not on tablets of stone but on tablets of human hearts" (2 Corinthians 3:3). Do you see the glory of this? The same Holy Spirit, the very finger of God, who wrote the law on stone at Sinai, is the one who, in the new covenant, writes that very same law on the hearts of believers.
The law has not been abolished; it has been internalized. The law has not been set aside; it has been resurrected. It was crucified with Christ, that handwriting of ordinances that was against us, and it was raised with Christ to be our delight. What was once an external accuser becomes an internal guide. What was once a ministry of death becomes the pathway of life. For the unbeliever, the entire Bible is law, condemning him. For the believer, the entire Bible, including the law, is gospel. It is good news that God has not only told us how to live but has also given us a new heart and His own Spirit so that we might walk in His statutes.
This is the autograph of God, first on stone, and now, by grace through faith in Jesus Christ, on the fleshly tablets of your heart. He has signed His name on you. He has claimed you as His own. And He is the one who will finish the inscription He has started, conforming you day by day to the image of His Son, until the law is your perfect liberty and obedience is your native tongue.