On the second day of creation, God divided waters from waters by making what Genesis calls the firmament. He named it Heaven, and the rest of the chapter describes the lights in the firmament and the birds flying across its face. I understand the firmament to be the expanse God actually made, although I do not think these passages give us every detail we might want about its physical structure.
The Separation God Made on the Second Day
Before the firmament appears in the account, God had already made light and divided it from darkness. Genesis then records another separation, this time involving the waters. Let’s read what God commanded and what Moses says happened in response:
Then God said, “Let there be a firmament in the midst of the waters, and let it divide the waters from the waters.” Thus God made the firmament, and divided the waters which were under the firmament from the waters which were above the firmament; and it was so. And God called the firmament Heaven. So the evening and the morning were the second day.
God commanded the firmament to divide the waters, and then the account tells us that He made it and accomplished that separation. Waters were beneath it, and waters were above it. Moses also records the name God gave it. The One who made the firmament had the authority to name it Heaven and to establish what it would do within His creation.
I take this as an account of something God brought into existence. If I reduce the firmament to an undefined symbol for order, I have lost the action the passage describes. God made something and used it to divide waters. I can affirm that without claiming that Moses has answered every question about what the expanse is made of or how we would describe its structure in modern terms.
The Hebrew word translated “firmament” is raqia. It is related to the verb raqa, which can describe spreading something out or beating it out, as a worker might hammer metal into a thin sheet. That connection helps us understand why “expanse” is used to explain the word. It carries the sense of something extended or spread out.
The connection with a verb used for hammering metal does not, by itself, tell me that the firmament is made of metal. To decide what a noun describes, I also have to read how it is being used in the passage. Genesis tells us that the firmament divides waters and that God called it Heaven. Those statements give us something definite to work with, but they do not provide a complete description of its material properties.
The older English word “firmament” can bring a hard dome to a reader’s mind. I want to be careful about how much of that picture I bring back into Genesis. The passage does not describe the edges of a roof resting on mountains, and it does not name lesser gods holding that roof in place. Adding those details and then arguing about them would move us away from the account Moses actually gave. My starting point is the real expanse God made and the purpose He stated for it.
What Scripture Calls Heaven
Since God named the firmament Heaven, we also have to consider how that name is used. The Hebrew word shamayim can refer to the sky where birds fly, the heavens where the lights are seen, or heaven as God’s dwelling place. The context tells us which use is intended. We use “heaven” in more than one way in English too, so recognizing a familiar word is only the beginning of understanding a particular verse.
We can see why that distinction helps when we continue through Genesis 1. On the third day, God gathered the waters under the heavens so that dry land appeared. He named the dry land Earth and the gathered waters Seas. On day four He appointed the heavenly lights, and on day five He commanded birds to fly across the face of the firmament. The account follows God’s work as He prepares the world and then fills it with living creatures.
Pay attention to what He says the lights are for. They give light on the earth, divide day from night, and mark signs and seasons as well as days and years. God assigned them those purposes. They do not appear as rival powers that He had to defeat before He could establish His rule. Throughout the account, He speaks and what He commands comes to pass.
I want to understand those stated purposes before asking the passage to answer questions it does not address. Genesis makes definite claims about God’s work, so I do not dismiss it as though it had nothing to say about the real world. Yet Moses is not giving us all the categories or measurements that we would expect in a modern account of atmospheric or astronomical processes. If I insist on finding those details in every sentence, I may stop paying attention to the explanation that is actually there.
The Waters Above the Firmament
The waters beneath the firmament are connected with the waters God gathered into seas on the following day. The waters above it leave us with further questions. Clouds carry water and bring rain, so I understand why someone would connect them with the upper waters. I do not think that settles the question entirely, because Scripture also speaks of waters above the heavens in a later passage:
Praise Him, you heavens of heavens, And you waters above the heavens!
Psalm 148 calls the heavens of heavens and the waters above the heavens to praise the Lord. The psalmist is calling God’s creation to honor its Maker, so I understand these waters as belonging to the real creation He rules. Their mention is not confined to the opening chapter of Genesis. At the same time, the psalm does not give their precise location or explain their physical condition. I can receive what it says without pretending that it supplies those additional answers.
Peter refers to water in another discussion of the world’s beginning. In 2 Peter 3:5, he describes the ancient heavens and the earth standing out of water and in water by God’s word. To understand why he brings that up, we have to look at the people he is answering. They question the promise of the Lord’s coming because they assume that things will continue as they always have. Peter answers by pointing them to creation and then to the Flood.
The world existed because God had spoken, and the Flood was a judgment that God had already brought upon it. The scoffers’ confidence depended on disregarding those events. Peter then explains that the present heavens and earth are preserved by the same word and are being kept for future judgment. The Creator has neither lost authority over His world nor left it to continue independently of Him.
I do not read Peter’s explanation as a missing diagram of the firmament. He is addressing the assumption that God’s future action can be dismissed because people expect ordinary life to continue. His reference to creation gives the reason that assumption fails: the world had a beginning through God’s word, it has already experienced His judgment, and it remains under His authority. That is the argument I want to carry forward when comparing his words with Genesis.
The Waters Remain Under Their Maker’s Authority
God’s authority over the waters also appears in His answer to Job. Job had suffered terrible losses and had asked questions about the way God governed his life. When the Lord answered him from the whirlwind in Job 38, He began asking Job about the creation of the earth. Job had not been present when its foundations were laid, and he could not explain all the work of the One he was questioning.
The Lord then spoke about the sea. He described shutting it in with doors, and He told Job that He had determined the limits of its advance:
When I fixed My limit for it, And set bars and doors; When I said, “This far you may come, but no farther, And here your proud waves must stop!”
The language of bars and doors makes the restraint understandable. The sea’s waves were subject to a limit God had established. Job could observe the water, but he had not created it or given it its place. The questions exposed the difference between what Job could see and what he actually understood about God’s government of the world.
This passage does not explain the physical structure of the firmament either. Its connection with Genesis is the authority of the Creator over the waters He made. God was not asking Job’s permission to rule, and He did not give a separate explanation for every loss Job had suffered. He showed Job that the wisdom required to govern creation exceeded Job’s understanding of it.
I need that correction when I begin treating my own understanding as the measure of what God ought to do. A limit can frustrate me because I would prefer to make the decision myself. Yet Genesis places God’s ordering of the waters before sin entered human life, as part of the world He prepared for His creatures. I therefore have no reason to assume that a boundary is hostile simply because God established it and I did not.
What the Firmament Tells Us About God
The creation we cannot fully explain still tells us something about the One who made it. David begins Psalm 19 by directing our attention to that testimony:
The heavens declare the glory of God; And the firmament shows His handiwork.
The firmament shows God’s workmanship. It belongs to the creation, and its existence directs attention to its Maker. If I worship the sky itself, I have given a created thing the honor that belongs to God. David’s words invite me to recognize whose work I am seeing and to respond to Him.
Paul develops that same responsibility in Romans 1. He explains that God’s invisible attributes, including His eternal power, can be understood through what He has made. People can suppress that knowledge and refuse to thank Him, but their refusal does not remove the testimony. Paul describes people turning from the Creator to worship created things, which shows how badly the response can go wrong even while the evidence remains before them.
I find it helpful that Psalm 19 does not stop with the heavens. David goes on to speak about the perfection of God’s law and the wisdom His testimony gives. Creation truly bears witness to God, and His written Word gives the further revelation we need. Scripture identifies the Savior and explains how sinners can receive forgiveness. A person can become absorbed in explaining the sky while remaining unwilling to listen to the God whose work it displays. I do not want my interest in creation to become a way of avoiding Him.
The Expanse in Ezekiel’s Vision
Ezekiel also uses the word firmament, but he is describing a vision rather than recounting the second day of creation. He was a priest among the Judean captives by the River Chebar, far from Jerusalem and its temple. There, in the land of the Babylonians, the heavens opened and he saw visions of God. Captivity had removed him from his homeland, but it had not put him beyond the Lord’s reach.
As Ezekiel describes what he saw, he repeatedly uses comparisons. He speaks of a likeness or says that something appeared like something else. Those expressions help his readers understand the vision without claiming that every comparison identifies the exact material of the thing described. Above the living creatures, he saw this:
The likeness of the firmament above the heads of the living creatures was like the color of an awesome crystal, stretched out over their heads.
The expanse was stretched out over their heads, and its appearance reminded him of an awesome crystal. Ezekiel then continued his description by looking above that expanse:
And above the firmament over their heads was the likeness of a throne, in appearance like a sapphire stone.
The description moves from the living creatures to the firmament over them and then to the throne above it. Ezekiel goes on to describe the appearance of the Lord’s glory. When he saw it, he fell on his face and heard the voice of the One speaking to him. The arrangement he describes directs our attention upward to the Lord who rules over His creatures.
I think we also need to remember where Ezekiel was when he received that revelation. Babylon had taken captives from Judah, but the God of Israel had not become subject to Babylon’s rulers. He could reveal His glory and speak to His servant in the land of exile. The vision shows His exalted authority, and Ezekiel’s response shows the reverence with which that revelation was received.
The Sea of Glass Before the Throne
John records a throne scene in Revelation 4 that invites comparison with Ezekiel’s vision. After the messages to the seven churches, John saw a door standing open in heaven and heard a voice calling him to come up. He was immediately in the Spirit and saw a throne with One seated on it. Other thrones surrounded it, and living creatures were there as well. Before the throne, he saw this:
Before the throne there was a sea of glass, like crystal.
John’s comparison with crystal reminds us of Ezekiel’s description, but we should also notice how each writer locates what he sees. Ezekiel describes the firmament above the creatures and the throne above that expanse. John describes a sea of glass before the throne. He does not call that sea the firmament. The resemblance gives us a reason to compare the passages, while their own wording tells us how far the comparison can go.
Revelation communicates through visions and symbols, often drawing on language found in earlier Scripture. That form of prophecy is sometimes called apocalyptic prophecy. Recognizing the form does not mean that the revelation is untrue. It means that I need to read the comparisons and symbols as part of the way God has chosen to reveal what John saw. In this scene, the living creatures continually declare God’s holiness. I understand the crystal-like sea as expressing the majesty and purity of His presence, and I also see in it a suggestion of holy separation before Him.
That is an interpretation of the scene, and I want to identify it as such. Genesis states that God made the firmament to divide waters. Ezekiel and John describe what they saw near God’s throne. I cannot simply take the water from Genesis, the expanse from Ezekiel, and the glass from Revelation and treat the result as a complete physical diagram supplied by all three writers. Each passage has to retain the setting and the explanation it actually gives.
Isaiah 66:1 helps us keep the Lord’s authority in view as well. He calls heaven His throne and earth His footstool, and then asks what house people could build for Him. He made the things out of which such a house would be built. His rule therefore does not depend on creation providing Him with a place to exist or permission to govern it.
Keeping Our Explanations Accountable to Scripture
These passages give me a reason to be careful both about dismissing Genesis and about adding to it. If someone begins by deciding that the account must be primitive error, he may end up criticizing a reconstruction that contains details Moses never supplied. Genesis does not describe gods of the sky and sea fighting for control. The one God speaks, makes the firmament, and assigns its purpose. Any criticism of the account needs to address those claims.
I need the same honesty when offering an explanation of my own. We can discuss clouds, the atmosphere, outer space, and the physical processes within creation. Those discussions can be useful. But if someone questions my proposed model, I cannot automatically accuse him of rejecting the words of Scripture. I first have to show which statements come from the passage and which parts belong to my explanation of it.
The throne visions call for that care too. Their descriptions reveal God’s glory, and I want to receive them with the reverence their writers express. Using them to make sensational claims about features of the universe they never describe would give my additions an authority they do not have. I can believe that the visions truly reveal what God intended without claiming that they answer every question I bring to them.
Responding to the Creator Who Reveals Himself
I live beneath a sky I did not make and on an earth whose existence did not depend on me. Studying them can increase my understanding, but it cannot give me authority over their Maker. Genesis tells me that God acted supernaturally through His spoken command. My attempts to explain His work remain accountable to what He has revealed about it.
The witness of creation also leaves me with a personal responsibility. Acknowledging that God made the heavens does not remove the sins I have committed against Him. The sky can display His workmanship, but looking at it cannot reconcile me to Him. For forgiveness, I need the Savior whom His written Word reveals.
Jesus Christ is the eternal Son through whom all things were made. He entered His own creation by becoming truly human, lived without sin, and willingly gave Himself to be slain as the perfect sacrifice for the whole world. Wicked men inflicted the bodily torture and death He suffered. The saving worth of His sacrifice rests on His perfection and on the blood and life He offered for us.
That offering was complete through His shed blood and death, before His burial and bodily resurrection. The Father did not punish, curse, abandon, strike, bruise, or pour wrath on Jesus. The Father and Son were united in the work of redeeming sinners, and the Son rose bodily after completing the sacrifice through which forgiveness is provided.
God’s offer of salvation is genuine and open to everyone, though people can resist and reject Him. Whoever repents and believes in Jesus is forgiven and justified, which means declared righteous before God. The Holy Spirit gives that person new life, dwells within him, and seals him for redemption. Every genuine believer is eternally secure because salvation rests on the work Christ has completed.
That security gives me a reason to depend on Him, not permission to live lawlessly. Calling myself a Christian does not establish that I have received new life, and obedience cannot purchase the life He gives. It is the response that should grow from belonging to Him. The Creator whose authority we have seen throughout these passages is also the Redeemer before whom I must answer.
The creation account continues in A Complete Bible Study on the Literal Six Days of Creation. For a fuller examination of creation’s witness, see A Bible Study on How to Prove the Existence of God. Another related study of the world Scripture describes is A Complete Bible Study on Giants in the Bible.
My Final Thoughts
The firmament is the expanse God made to divide the waters, and He named it Heaven. Genesis presents that work as something He actually accomplished. The Psalms call His creation to praise Him, while Ezekiel and John show His glory through the throne visions they received. Those passages give me confidence in the Creator’s authority even where they leave questions about the physical details unanswered.
I want that confidence to make me more willing to listen to what God has said and more careful about what I add. His handiwork deserves study, but the honor belongs to Him. The Son through whom the heavens were made also gave His life to redeem us, so my response cannot end with an argument about the sky. I owe my life to its Maker, and I trust His Son for the forgiveness I could never provide for myself.