God’s Incommunicable Perfections

Catechetical sermons preached in PCC Evening Worship Services, Feb 2013 to Dec 2017

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13 And Moses said unto God, Behold, when I come unto the children of Israel, and shall say unto them, The God of your fathers hath sent me unto you; and they shall say to me, What is his name? what shall I say unto them? 14 And God said unto Moses, I AM THAT I AM: and he said, Thus shalt thou say unto the children of Israel, I AM hath sent me unto you. 15 And God said moreover unto Moses, Thus shalt thou say unto the children of Israel, The LORD God of your fathers, the God of Abraham, the God of Isaac, and the God of Jacob, hath sent me unto you: this is my name for ever, and this is my memorial unto all generations.”

Exodus 3:13-15

Q4. What is God? A. God is a Spirit,1 infinite, 2 eternal, 3 and unchangeable, 4 in His being, 5 wisdom, 6 power,7 holiness, 8 justice, 9 goodness, and truth. 10  

1 Jn 4:24;  2 Job 11:7–9;  3 Ps 90:2;  4 Jas 1:17;  5 Ex 3:14; 6 Ps 147:5;  7 Heb 1:3;  8 Rev 4:8;  9 Rev 15:4;  10 Ex 34:6–7. 

Moses was a proud man. But he is proud no more. The LORD humbled him. It took forty years of solitude in the pasture lands of Midian. But he was now ready to be used by the Lord. 

For the first forty years of his life, Moses grew in significance and, no doubt, pride in Egypt’s wealth and worldly wisdom. 

Moses became so self-confident that he was sure the Hebrews would agree that he was the best person to lead them out of Egypt. So confident was he that he went down to visit his people to see how he could help them. But in his impulsiveness, he killed an Egyptian. Then when it became clear that the Hebrews were not going to stand with him, he was forced to flee.  

He fled to Midian, where for forty years, he would work as a humble shepherd. For forty years, the LORD would chip away at his pride, little by little. 

Forty years later, Moses was ready for the LORD’s work. The LORD called him from the burning bush and told him to return to Egypt to lead His people out. Moses’ immediate response was: “Who am I?”— “Who am I, that I should go unto Pharaoh, and that I should bring forth the children of Israel out of Egypt?” (v. 11). 

Moses has lost his self-confidence. Forty years ago, he would have said (at least in his heart), “Hey, I am indeed the right one for the job!” And now, when the LORD is finally calling him to the work, we might expect him to say: “Finally, what I have been waiting for all these years!” But no, his reply was incredulous. “Who am I? Who am I that I should go unto Pharaoh? Who am I that I should bring the children of Israel out of Egypt?”  

Moses was feeling very small and inadequate for the task. The LORD assured him that He would be with him and even gave him a sign to assure him. But Moses was still reluctant to go. In fact, he would later explicitly request the Lord to send someone else (Ex 4:13). 

But for now, almost as if to buy time to think of a good excuse, Moses asks the LORD: 

Behold, when I come unto the children of Israel, and shall say unto them, The God of your fathers hath sent me unto you; and they shall say to me, What is his name? what shall I say unto them?” (v. 13). 

Egypt had a pantheon of deities, each with names such as Anubis, Apis, Apepi, Babi, Bastet, Cherti, Dua, Geb, Horus, Hapi, Ibis, Imhotep, etc. No doubt, Moses knew that God is the alone, living and true God; but he thought it best to be able to answer the people if they should ask him for the name of the God who is sending him. 

Whatever the case, God honours his question and answers him fully. In His answer, He gives us a most remarkable revelation about Himself, Exodus 4:14: 

And God said unto Moses, I AM THAT I AM: and he said, Thus shalt thou say unto the children of Israel, I AM hath sent me unto you.” 

What is the name of God? “I AM THAT I AM,” He says. From this time onwards, God’s people would know God as the “I AM.” “This is my name for ever, and this is my memorial unto all generations,” says the LORD (v. 15). 

The Jews do not call Him ‘I AM’, but according to the Hebrew way, they call Him ‘HE IS’. It is like I am ‘I’, but when you speak to me, you will address me as ‘you’, and when you speak about me to someone else, you will refer to me as ‘he.’ 

Now the Jews refer to the LORD as ‘HE IS’ since He introduced Himself as ‘I AM.’ So ‘HE IS’ became the name of God. Now the word for ‘HE IS’, as it is used for the name of God in the Old Testament, has four consonants in the Hebrew— הוהי (pronounced, yodh-hey-vav-hey, reading right to left). This word is known as the Tetragrammaton.  

Now, the Jews traditionally do not pronounce the Tetragrammaton as they are afraid they may take God’s name in vain if they pronounce it. So whenever they read the Scriptures and come across the Tetragrammaton, they usually read it as ‘adonai’, the Hebrew word for ‘Lord.’ This is why in the English Bible, it is usually translated as ‘LORD’ in full caps to distinguish it from the word for ‘adonai.’1  

But the Tetragrammaton is translated as ‘Jehovah’ seven times in the KJV (Gen 22:14; Ex 6:3; Ex 17:15; Judg 6:24; Ex 6:3; Isa 12:2; Isa 26:4), and so English-speaking Christians know the LORD as Jehovah.  

How do we get the name “Jehovah”? Jehovah is not Hebrew; it is an English rendering of the Tetragrammaton! It is produced by combining the four consonants of the Tetragrammaton with the vowel sounds of the word ‘adonai.’  

In any case, we must understand that Jehovah is the same as the LORD or the “I AM” or “HE IS.” Jehovah is the English rendering of the name of God.2 

Now, in this sermon, the LORD helping us, we must consider briefly what He would have us learn from this name that He has chosen to have us know Him by.   

So what would the Lord teach us by this name, “I AM” or Jehovah? Well, there are several things that we may learn from it. But we are in a series of messages on the Westminster Shorter Catechism, and we are considering Question 4, where we are taught that “God is a spirit, infinite, eternal and unchangeable in his being, wisdom, power, holiness, justice, goodness and truth.” 

We have seen how God is spirit. He does not have a body, and he has no locality. In this follow-up study, we must look at His incommunicable attributes or perfections, namely, His infinitude, eternality and unchangeableness. These three attributes are implied by the LORD’s self-introduction, “I AM THAT I AM.” 

Consider first how God is self-existent and, therefore, eternal. 

1. He Is Eternal 

The first thing that is immediately implied by the LORD when He introduces himself as “I AM THAT I AM” is that He is self-existent. When God says, “I am that I am,” He is declaring: “I exist in and of myself; I depend on no one for my existence.” All things in the universe exist because the LORD made them, but He Himself is not made. He exists in and of himself.  

And if God exists in and of Himself, He must be eternal; that is, He must have no beginning and no end. Think about it. Something that exists and is not made has to be eternal. Only things that are made have a beginning. Therefore, things that are not made have no beginning. They are eternal. This is why those who do not believe in the existence of God must somehow agree that matter must be, in some sense or form, eternal. What exists in and of itself must be eternal. So God is declaring His eternality when He says He is the “I AM.” 

Thus, Moses calls Him the “eternal God” (Dt 33:27). “The eternal God is thy refuge, and underneath are the everlasting arms,” he says. 

God alone is eternal because everything else has a beginning. When Scripture opens by saying, “In the beginning God created the heaven and the earth” (Gen 1:1), it is declaring that God makes everything that exists in the spiritual and the physical realms. Only God is unmade. Only God is eternal. 

What about angels and men? Does not man have an eternal soul? Do not angels have eternal existence? Well, let us understand that man and angels are not eternal in the sense that God is eternal. 

In the first place, both angels and men have a beginning. Angels were made on the first day; man was made on the sixth day of creation. 

In the second place, both angels and men, being creatures, are sustained in existence by God. Paul says: “For in him we live, and move, and have our being” (Acts 17:28). The apostle to the Hebrews says that Christ upholds all things by the word of His power. We are not only made, but exist and continue to exist because God holds us in existence.  

You see, God’s eternality is an incommunicable perfection. Only God can be eternal because God alone is self-existent. 

But secondly, in saying that He is the ‘I AM’, The LORD is saying He is unchanging. 

2. He Is Unchanging 

When the Lord says that He is the I AM, He is also saying, “I was,” “I have always been,” “I shall be,” and “I will always be.” Then by implication, He is also saying: I am what I was; I shall be what I am. In other words, God is saying: “I change not.” 

Thus, in Malachi 3:6, God says, “I am the LORD [Jehovah], I change not; therefore ye sons of Jacob are not consumed.” 

Now, this is a remarkable declaration. God is essentially saying that because He is the I AM, He changes not.  

God is not like man, who is constantly changing. Man is a finite creature that increases in knowledge moment by moment. You have changed from one minute ago. Not only has your molecular and cellular composition changed, but you have also changed in terms of your knowledge. You now know, for example, that you were alive 30 seconds ago. One minute ago, you would not have that knowledge.  

Not only do you change by increasing in knowledge. You also change by changing your mind, and you change your mind all the time. You change according to your circumstance, your understanding and your feelings. One moment you respect someone; the next moment, you can despise him. One moment you love someone; the next moment, you can hate him. Of course, most of us are not so flippant as to change drastically like an octopus, but still, it is a fact that we change our minds all the time. 

God is not like that. God is unchanging. He is immutable. This truth is taught in several places in Scripture. For example, turn to Numbers 23:19. 

Here, the pagan prophet Balaam, inspired by the Spirit of God, says:  

“God is not a man, that he should lie; neither the son of man, that he should repent: hath he said, and shall he not do it? or hath he spoken, and shall he not make it good?” (Num 23:19). 

Balaam was employed by Balak, the Moabite king (Num 23:16). Israel had just defeated Sihon, king of the Amorites and Og, king of Bashan (Num 21:21-35). She was then pitched in the Plains of Moab (Num 22:1). Balak heard all these things and was afraid that the Israelites might attack Moab too. So he hired Balaam to curse them, hoping it might spell their defeat.  

Balaam, at first, refused to do as Balak requested. But eventually, perhaps due to greed, he consented to go. Nevertheless, the LORD would not allow curses to come out of his mouth, only blessings. Balak chided him, and he tried again. It was in the context of this second attempt to curse Israel that those beautiful words of affirmation flowed. 

God is not like man. Man changes. Even the most well-meaning man can change. God is not like that. He will never change His mind because He is immutable. 

For this reason, God’s children can be absolutely sure that God will keep all His promises, unlike man. Man can change his mind about keeping his promises, or he may find himself powerless to fulfil what he has promised. But not God. 

No one else is like God. God’s immutability or unchangeableness is another of His incommunicable perfections. 

But now, thirdly, when the LORD introduces himself as the I AM, He is also alluding to the fact that He is infinite. 

3. He Is Infinite 

We have seen that when the LORD introduces Himself with the words “I AM THAT I AM,” He is saying He is eternal and unchanging. 

But if God is without beginning and without end, and He does not change, whether for the better or for the worse, for all eternity, then it must follow that He is perfect. God cannot become worse, or He will cease to be God. And since God is in absolute control of all things, and yet He cannot become better, it must follow that He is perfect.  

Now, for God to be perfect, He must be infinite in every way. That is to say, He is not limited or bounded in any way.  

Zophar, the friend of Job, alludes to this fact in Job 11:7. He says— 

“Canst thou by searching find out God? canst thou find out the Almighty unto perfection? 8 It is as high as heaven; what canst thou do? deeper than hell; what canst thou know?” (Job 11:7-8) 

Zophar is essentially saying that God is perfect and infinite, and, therefore, cannot be fully comprehended by finite beings. 

The infinitude of God is spoken of in numerous other passages in Scripture.  

For example, Solomon alludes to God’s infinity of being when he asserts that “the heaven and heaven of heavens cannot contain him” (2 Chr 2:6).  

Likewise, the psalmist affirms in Psalm 147:5, “Great is our Lord, and of great power: his understanding is infinite” (Ps 147:5).  

Similarly, when the cherubim in the hearing of Isaiah proclaimed, “Holy, holy, holy, is the LORD of hosts” (Isa 6:3), they testify that Jehovah is infinite in holiness.  

God alone is infinite. He is infinite in all His attributes. Man is finite. Angels are finite. Infinitude is one of the incommunicable attributes of God.  


The living and true God is not only a spirit. He is the I AM. We have seen how, by this name, God reveals himself to be infinite, eternal and unchangeable. We call these His incommunicable attributes or perfections because no man or angel shares these attributes to any degree. All creatures are finite and can get better. All creatures have a beginning and are held in existence by the power of God. All creatures can and do change. 

God alone is infinite, eternal and unchangeable. And these incommunicable attributes of God qualify all the communicable attributes of God.  

So, God is infinite, eternal and unchangeable in being. So, God is also infinite, eternal and unchangeable in wisdom. So, God is also infinite, eternal and unchangeable in power. So, God is also infinite, eternal and unchangeable in holiness.  

We have a measure of the communicable attributes of God, such as being, wisdom, power, and holiness. But we do not have His incommunicable attributes, such as infinitude, eternality and immutability. These are the perfections that qualify God as God. 

But how should we respond to this knowledge of God?  

First, as we begin to apprehend God’s infinitude, let us again remind ourselves of our creatureliness and finitude. Whereas God is infinite and perfect, we are creatures of dust who are weak, frail and imperfect in every way. We have no reason to be proud, and yet we are proud. We often have too high an estimation of ourselves—like Moses in his earlier years. 

Solomon built a glorious temple, and he knew that even the heaven and heaven of heavens could not contain God. So he humbly asked God to accept the work of his hand and to look upon him and his people with pity. What about you? The holy angels covered their faces and feet as they ministered before God. What about you? What is your attitude towards your infinite God? May we respond with humility, awe, wonder, fear and reverence. Oh, may the Lord grant that we may learn humility in less than forty years! 

Secondly, as we are confronted with the eternality of God, let us remind ourselves of how undependable and temporary man is. We are here today, gone tomorrow. If we live to please man or find our chiefest joy in fellow men, we will be sorely disappointed.   

Moses had begun as a very self-assured and self-confident man. As a young man, he thought that his kinsman would appreciate his gifts, and so he sought to please them. It took forty years of humbling, and another almost forty years of experience for Moses to learn to put His trust only upon the eternal LORD, the I AM. 

Moses was reflecting on the eternality of God in Psalm 90. This Psalm was written, no doubt, towards the end of the forty years of wandering in the desert. Many of the Israelites died in the wilderness. No one was untouched by the sorrows of death and separation. At such times, what solace and comfort can we find? Moses teaches us to find our comfort in the eternal God. So the Psalm begins: 

“Lord, thou hast been our dwelling place in all generations. 2 Before the mountains were brought forth, or ever thou hadst formed the earth and the world, even from everlasting to everlasting, thou art God” (Ps 90:1-2). 

Beloved brethren and children, life is full of uncertainty. Nothing under the sun is permanent. Therefore, set your affection on the Lord and on things above. Only God is eternal. Only God is permanent. 

But now, thirdly, as we appreciate that God is unchanging, let us learn to thank Him for His promises. God is not a man that He should change His mind about His promises. Has He promised, He will see to it? Rest upon His word and find your solace and encouragement in Him. 

But finally, as we contemplate the fact that God is infinite, eternal and unchangeable, let us remind ourselves of the great distance between God and us. Then let us fill our hearts with praise and thanksgiving that He has entered into a covenant relationship with us so that we can have joy and fruition with Him.  

And let us thank Him for the Lord Jesus Christ, the Immanuel, the God-Man. Christ came not only to pay for our sins. He came also to bridge the immense chasm between God and us. And He came also that He might be a compassionate Great High Priest to us—that God may personally experience our frailty and demonstrate His love and compassion toward us. Were it not for the Lord Jesus Christ, we can have no confidence that God understands us. Were it not for the Lord Jesus Christ, we could have no relationship with God. Thank God for Christ, the only Mediator between God and Man. May the Lord grant that we may all believe Him and love Him. He says: “I am the way,  the truth, and the life: no man cometh unto the Father, but by me” (Jn 14:6). Amen. 

—JJ Lim 

1This is how the word is translated 6510 times. Well, sometimes the word adonai occurs before the tetragramaton, then the Jew would read it as Adonai Elohim. Elohim is ‘God’ in Hebrew. Thus the tetragrammaton is sometimes translated as G-O-D. This accounts for 304 occurrences of the word.

2Some argue that we should instead call Him ‘Yahweh’. But no one knows if that is the correct pronouciation either. Besides, those who insist on using Yahweh should perhaps refer to Jesus as “Yesus” or even“Yehoshua.”