Deuteronomy chapter four is one of the great touchstone passages in all of Scripture. As we come to this passage, my heart and soul are absolutely struck by the question–a rhetorical question, but a very real question–asked in verse 33: “Has any people heard the voice of the Lord, the voice of God speaking from the midst of the fire, and survived?”

What brings us here? What brings us to this institution, to this campus, to this hour, ready for learning and study? Something summons us here. There is some mandate, some basis, some foundation. This is a theological seminary and college. We dare to speak of God. We even dare to define what we do here as Christian education. What an audacious claim! We actually say that here we teach what God has taught.

This would be a baseless and foundationless claim, an incredible claim, if God had not spoken from the midst of the fire and allowed us to hear. On what authority are we here? To dare to speak of these things, we must speak invoking the authority of God, who alone could speak these things, reveal Himself, and tell us what we must know. This is the answer to the question that haunts the postmodern mind–on what basis can we claim to know anything?

The great philosophical crisis of our day is an epistemological crisis. It is a crisis of knowing, a crisis of knowledge. In particular, it is a challenge for Christianity and for the Christian thinker, the Christian theologian, the Christian minister, the Christian preacher, and the Christian institution. How do we know what we claim to know? How dare we teach what we dare to teach? As Francis Schaeffer understood well, and he took the answer as the title of his most significant contribution: We speak because He Is There and He Is Not Silent.

I first read that book as a sixteen-year-old, and to be honest, I think the greatest assurance I got from it is that some smart person believed in God. Even at that age, however, and lacking the vocabulary to understand what I was experiencing, I understood the epistemological crisis. How do we know anything? How can we speak of anything? And furthermore, how do we jump from the empirical knowledge of what we can observe to speaking of God whom we cannot see? To claim knowledge in terms of empirical and scientific observation and study and phenomenology is audacious enough. But to speak of the immortal invisible God only wise–that is a new leap of audacity altogether. Dr. Schaeffer understood the epistemological problem of silence, the claim and the implication that we can know nothing. And he understood that there is only one epistemological answer–revelation. Thus Christianity depends upon a Christian epistemology or a Christian theory of knowledge that is based in revelation alone.

There is no greater challenge than this–to make certain that we know on what authority we speak, and that we know on what authority we know. In Deuteronomy chapter four, Israel is reminded of the authority by which they live. They are reminded that they heard the voice of God speaking from the midst of the fire and survived.

This great sermon, of course, comes at the conclusion of the introductory section to Deuteronomy. It begins and ends with a parallel structure, and in the middle is a large section reflecting the form of a suzerainty treaty, an Ancient Near Eastern convention whereby a conqueror sets down the terms of surrender. In this case, of course, the conqueror is none other than the Lord God Jehovah, the conquered is none other than His own chosen nation, Israel. God sets down the terms, and they are very easy to understand. It comes down to a very simple formula: hear and obey and live. Refuse to hear, disobey, and bear the wrath of God.

In this tremendous sermon, God speaks through His servant and prophet Moses. Looking back to the covenant at Horeb, obedience equals blessing, and disobedience equals cursing. This generation ought to know that. For this is the generation that survived, that was kept alive, through forty years of wandering in the wilderness. They had witnessed the death of their own parents because they disobeyed and did not trust the Lord. And now as the children of Israel are being prepared for the conquest of the Holy Land, they are reminded that they heard the voice of God speaking from the midst of the fire and survived. As the Lord is preparing this new generation, we find in this sermon exhortation and memory mixed together–the memory of God’s great saving work in bringing Israel out of captivity to Pharaoh in Egypt, and the great work of God in keeping the children of Israel alive through the forty years of wandering in the wilderness.

We call this book Deuteronomy–deutero nomos–the second giving of the law, because in the very next chapter we will confront again the Ten Commandments. The theme is very clear. Israel, in terms of its elect status, is the chosen nation of God, and that special status is represented in Torah, in this word, this law, even in these Ten Words. The central truth is that the Lord God spoke to His people, and they heard, and they survived. Moses says, “Remember the day you stood before the Lord your God at Horeb, when the Lord said to me, ‘Assemble the people to Me, that I may let them hear My words so that they may learn to fear me all the days they live on the earth, and that they may teach their children.’ You came near and stood at the foot of the mountain, and the mountain burned with fire to the very heart of the heavens: darkness, cloud, and thick gloom.”

The giving of the Ten Commandments cannot be separated from the narrative context in which it comes. The propositional truth which is in the law comes in the midst of a history of a people and God’s dealing with that people. It is a relational revelation, and it is a dramatic revelation. Israel is reminded not only of what they heard, but of the context in which they heard it. “The mountain burned with fire to the very heart of the heavens, darkness, cloud and thick gloom. Then the Lord spoke to you from the midst of the fire; you heard the sound of words, but you saw no form–only a voice. So He declared to you His covenant which He commanded you to perform, that is, the Ten Commandments; and He wrote them on two tablets of stone.” The Lord God spoke to you from the midst of the fire. You heard the sound of words, but you saw no form, only a voice. A voice!

Israel, heard the Lord, but they did not see Him. This is not a God who is seen, but a God who is heard. The contrast with the idols is very clear. The idols are seen, but they do not speak. The one true and living God is not seen, but He is heard. The contrast is intentional, it is graphic, and it is clear. We speak because we have heard.

The theme of these verses, especially in verses ten through thirteen, is the sheer gift of this. The revelation of God is sheer mercy. We have no right to hear God speak. We have no claim upon His voice. We have no right to demand that He would speak. We are accustomed to pointing to the cross of Christ and saying, there is mercy! But at Horeb, too, there was mercy. There is mercy whenever God speaks. There is the danger that contemporary evangelicals think of the doctrine of revelation primarily as an epistemological problem. Even those who hold to a high doctrine of Scripture–affirming the inerrancy of Scripture, verbal inspiration, propositional truth–are in danger of thinking of revelation primarily in epistemological terms. To be sure, there is an epistemological question, and there is an epistemological authority. But the reality is, this is mercy. It is a gift. Professor Eugene Merrill has said that while it is quite remarkable that no other nation had ever heard God speak out of the fire and lived to tell about it, the fact is, there are not even any other peoples that heard the voice of the Lord speak out of the fire and didn’t live to tell about it. The Lord God spoke uniquely and particularly to Israel and allowed them to survive.

The background to all this, of course, is the paganism of that day. The idols were many in those days, and all of them were silent. In fact, the silence of the idols is a pervasive biblical theme. Think of 1 Kings 18, and the battle of the gods and Elijah. Think of Elijah as he waits and watches the prophets of the Ashteroth and the Baal jumping around the altar and lacerating their bodies so that the blood flows down into the ground–all this to get Baal’s attention. But as we are told in 1 Kings 18, there was no voice. No one answered. No one paid attention. With the God of Israel, however, everything is different. The idols do not speak. The Lord God of Israel does. The idols are seen but not heard. God is heard but not seen.

But what if God had not spoken? What if we had not received this word? If God had not spoken, we might have a religion school. It might be that human beings, just in the blindness of trying to figure things out, would come to some sense of transcendence, and perhaps even be able to make some kind of argument from design. And certainly, human beings, possessing some ingenuity and intelligence, would be pondering these things. Of course, we need not speak hypothetically about this. We see it. All you have to do is listen to the cultural chatter, and you hear the kind of conversation that would take place if God had not spoken. Go to some divinity schools, some theological seminaries, some universities in the academic world, and you will see the kind of discourse and the kind of teaching and the kind of philosophy and worldview that would emerge if God had not spoken.

What if this really is a game that we are playing, each using whatever language game is convenient and handy in terms of our social and cultural and linguistic system? What if this really is something of a smorgasbord of worldviews in which we can just kind of put it all together as we see fit? If God has not spoken, then there is no end to that game. If God has not spoken, no one is right and no one is wrong. If God has not spoken, what you end up with is the end game of postmodernism–nihilism, no knowledge whatsoever.

But if God has spoken, everything is changed. If God has spoken, then the highest human aspiration must be to hear what the Creator has said. And though the revelation of God is not merely propositions, it is never less than that. It is personal. Hearing the voice of the Lord God is not merely to receive information, but to meet the living God. We are accustomed to speaking and singing of grace and mercy of God, and our redemption in the cross of Christ. But we must also speak of the mercy of God in revelation.

In the book of Deuteronomy, we meet the speaking God. “Has any people heard the voice of God speaking from the midst of the fire, and survived?” Mercy and grace meet here. This is, in its own way, a proto-gospel. Christopher Wright makes this comment concerning what happened at Sinai, saying what really mattered there was not that there had been a theophonic manifestation of God, but that there had been a verbal revelation of God’s mind and will. Sinai was a cosmic audiovisual experience, but it was the audio that mattered. It is the audio that matters, for God has spoken.