Marc Roby: We are resuming our study of systematic theology today by continuing to examine the Doctrine of the Trinity. We are following the outline in Wayne Grudem’s Systematic Theology, which states that to firmly establish this doctrine of the Trinity, we must establish three things: First, that God exists in three persons; second, that each person is fully God; and third, that there is one God. Now, we have shown that God exists in three persons and that each person is fully God. So, Dr. Spencer, I assume you want to begin by making the biblical case that there is only one God, is that right?
Dr. Spencer: That’s right. The fact that there is only one true and living God is an absolutely undeniable and consistent teaching of the Bible. And it has not been a controversial point either, so I don’t think we need to spend much time on it. But, there are some things it will be useful to point out.
In Chapter 12 of Mark’s gospel we read about a teacher of the law asking Jesus, “Of all the commandments, which is the most important?”  And we read Jesus’ famous answer in Verses 29-31, “The most important one is this: ‘Hear, O Israel, the Lord our God, the Lord is one. Love the Lord your God with all your heart and with all your soul and with all your mind and with all your strength.’ The second is this: ‘Love your neighbor as yourself.’ There is no commandment greater than these.” I want to focus on the first thing Jesus said, “Hear, O Israel, the Lord our God, the Lord is one.”
Marc Roby: Well, it would be hard to be clearer than that, “the Lord our God, the Lord is one.”
Dr. Spencer: I don’t think you can be any clearer than that. And Jesus was quoting the famous Shema from Deuteronomy 6:4. The word Shema is the first word of this verse in the Hebrew and means “hear”. It has been called the greatest confession of the Jewish faith and is recited daily by devout Jews even today. In fact, it is also recited at the climactic moment of the final prayer of Yom Kippur, the holiest day of the year, and traditionally as the last words before death. But, there is also something very interesting to say about the Shema given that we are discussing the Doctrine of the Trinity.
Marc Roby: What is that?
Dr. Spencer: When it says “the Lord our God, the Lord is one”, the Hebrew word translated here as “one” is echad, and James Boice says it “means not one in isolation but one in unity. In fact, the word is never used in the Hebrew Bible of a stark singular entity. It is the word used in speaking of one bunch of grapes, for example, or in saying that the people of Israel responded as one people.” The same word is used in Genesis 2:24 where we are told “For this reason a man will leave his father and mother and be united to his wife, and they will become one flesh.” When it says “one flesh”, the Hebrew word translated as “one” is again echad.
Marc Roby: That is very interesting, God is one, but not, as Boice puts it, “a stark singular entity”. What other biblical evidence do we have for the fact that there is only one God.
Dr. Spencer: In Isaiah 45:5-6 God tells us, speaking through the prophet, “I am the LORD, and there is no other; apart from me there is no God. I will strengthen you, though you have not acknowledged me, so that from the rising of the sun to the place of its setting men may know there is none besides me. I am the LORD, and there is no other.”
Marc Roby: That is again perfectly clear.
Dr. Spencer: Yes, it is. There really is no doubt that the Bible reveals that there is one and only one God, the Creator of this universe. And as we labored to explain earlier, the fact that there is only one God does not in any way, shape or form contradict the fact that he exists in three persons. It also makes perfectly good sense that God exists in three persons when you consider his personal nature, God is love, but it doesn’t make sense to speak of love if there is only one person. Obviously, we can talk about loving ourselves, but that is not the deepest or truest sense of the word. God exists in three persons and those three persons have had perfect mutual love and fellowship for all eternity. God didn’t somehow become loving when he created this universe and the animate creatures that inhabit it.
Marc Roby: Well, it appears that we have now demonstrated all three of Grudem’s points: First, that God exists in three persons; second, that each person is fully God; and third, that there is one God. So, have we finished with the Doctrine of the Trinity?
Dr. Spencer: Not quite. We’ve finished with making the biblical case in support of it, but I would like to add a couple of comments for those who really struggle with this.
There is a principle in science known as Occam’s razor, which says that all else being equal, we should always prefer the simpler of two competing theories. Now I happen to think this principle is a good one, but we need to be very careful to remember the “all else being equal” part. Whatever theory we choose must explain the observable facts. This is the Platonic idea that our theory must preserve the phenomena. The great English mathematician and philosopher Alfred North Whitehead once famously said that “The guiding motto in the life of every natural philosopher should be, ‘Seek simplicity and distrust it.’”
Marc Roby: That sounds like a good approach, things are not always simple, so we must be sure that a simple answer does, in fact, explain all the observable facts, as you noted.
Dr. Spencer: Yes, that is an extremely important point. The truth of the matter is that the world we live in abounds with evidence of complicated phenomena. There is no doubt, for example, that Newton’s law of gravitation is simpler than the theory of general relativity; but, there is equally little doubt that Newton was wrong and the theory of relativity is either correct, or at least much closer to being correct. You can ignore some of the data and think that Newton had it completely right, but when you seek to explain all of the observable data, you find that Newton’s simple theory won’t work.
So it is with the Trinity. The Bible provides us with ample evidence that the doctrine is true, even though it is extremely difficult to understand. You can ignore some of the data, or twist and distort the data as the Jehovah’s Witnesses do, but you aren’t being honest in seeking to understand the data when you do that. The Word of God is too important to treat that way, we must seek to know the truth to the best of our abilities, even if it is beyond us to fully comprehend that truth.
Let me close with a statement that sums it up well. I want to be clear that this isn’t entirely original, I’m modifying a statement attributed to a Dr. South, which was quoted by the 19th-century theologian William Shedd.  Anyone who denies the doctrine of the Trinity will lose his soul, but anyone who tries to probe beyond what Scripture teaches may lose his mind.
Marc Roby: Now that is a good statement! And it reminds me of Psalm 131:1, where David declares that “I do not concern myself with great matters or things too wonderful for me.”
Dr. Spencer: That is good counsel. There are some things that we either don’t have sufficient information to fully understand or are simply not capable of fully understanding. We are not called to believe anything that is truly contradictory, but it doesn’t follow that we should reject the truth of things we can’t fully understand. And in Deuteronomy 29:29 we are told that “The secret things belong to the LORD our God, but the things revealed belong to us and to our children forever, that we may follow all the words of this law.”
Marc Roby: And I would say that a full understanding of the Trinity would certainly qualify as one of those secret things.
Dr. Spencer: And I would agree. So, I think we are now done with the Trinity.
Marc Roby: Great. What do you want to look at next?
Dr. Spencer: Before we move on, let me very briefly review what we have already covered. We are covering the topic of theology proper; in other words, the nature of God as he has revealed himself to us in the Bible. We noted that God’s attributes can be loosely divided into his incommunicable attributes, that is those which we do not share, and his communicable attributes, which are those we share to some degree.
We also noted what is called the simplicity of God; that is, that he cannot be thought of as an assemblage of parts. We should never think of any attribute of God in isolation, he is all of them, all of the time, in every relationship. God’s simplicity is also sometimes called his unity. We also noted that we can only know what God chooses to reveal about himself and that we cannot relate to God as anything other than our Lord.
Marc Roby: Which is, I hasten to add, an extremely important point. We are not equals!
Dr. Spencer: No, we’re not even close. The Creator/creature distinction is, as we’ve noted multiple times, critically important. I keep harping on this because the modern church has lost sight of this fact; if not in theory, then at least in practice. You see that by the casual and careless way most professing Christians approach worship and the Word of God.
In any event, continuing with our brief review, we started with God’s incommunicable attributes and discussed his aseity, which means his self-existence. Then, most recently, we discussed his triune nature, which we noted is sometimes not considered an attribute, but is part of the nature of God’s being.
Marc Roby: Alright, I assume we are going to go on to look at other incommunicable attributes. Which one do you want to discuss now?
Dr. Spencer: Let’s look at the unchangeableness of God, which is also called his immutability. This is an extremely important attribute and it should provide great comfort to the Christian. We can be absolutely certain that God’s promises are true and unchangeable and that he himself is unchangeably capable of fulfilling them.
Marc Roby: That is a great comfort. And it is certainly taught in the Bible, which passage would you like to look at first?
Dr. Spencer: Let’s start with Numbers 23:19, where we read, “God is not a man, that he should lie, nor a son of man, that he should change his mind. Does he speak and then not act? Does he promise and not fulfill?” These are obviously rhetorical questions, so the point is that when God speaks, he will also act. And when he makes a promise, he will fulfill it, because he is unchangeable.
Marc Roby: It is fascinating to note that it was the false prophet Balaam whom God used to speak those very words.
Dr. Spencer: That is an interesting point, and it is a demonstration of the fact that God is sovereign over all, even his enemies.
But, getting back to God’s immutability, we learn about it in many other places as well. In Psalm 33 for example we are given a clear contrast between the plans of men and the plans of God. In Verses 10-11 we read, “The LORD foils the plans of the nations; he thwarts the purposes of the peoples. But the plans of the LORD stand firm forever, the purposes of his heart through all generations.” In other words, God is unchangeable. His plans and his purposes stand firm.
We see a similar contrast in Psalm 102, this time the contrast is between the changeable nature of the inanimate creation and the immutability of God. In Verses 25-27 we read, “In the beginning you laid the foundations of the earth, and the heavens are the work of your hands. They will perish, but you remain; they will all wear out like a garment. Like clothing you will change them and they will be discarded. But you remain the same, and your years will never end.”
Marc Roby: That is hugely comforting. Our sun and earth will one day perish, but our God and his promises to us will not, which means that we will not!
Dr. Spencer: That is great comfort. We will spend eternity with God in a new heaven and a new earth. The Lord’s brother, James, speaks about the unchangeable nature of God as well. In James 1:17 he wrote that “Every good and perfect gift is from above, coming down from the Father of the heavenly lights, who does not change like shifting shadows.” And God spoke through the Old Testament prophet Malachi saying, in Malachi 3:6, “I the LORD do not change. So you, O descendants of Jacob, are not destroyed.”
Marc Roby: Hallelujah! We are not destroyed because God’s eternal purpose of saving a people for himself will not change.
Dr. Spencer: You’re right, it will not change. In Isaiah 14:24 the prophet tells us that “The LORD Almighty has sworn, ‘Surely, as I have planned, so it will be, and as I have purposed, so it will stand.’” Which should be a great comfort to all who know Jesus Christ as Lord and Savior.
But, God’s unchangeable nature is a double-edged sword; it is also true that God will not fail to punish the wicked who refuse to repent and trust in Christ. In fact, the verse I just read is really directed to that end. The next verses, Isaiah 14:25-27, say, “‘I will crush the Assyrian in my land; on my mountains I will trample him down. His yoke will be taken from my people, and his burden removed from their shoulders.’ This is the plan determined for the whole world; this is the hand stretched out over all nations. For the LORD Almighty has purposed, and who can thwart him? His hand is stretched out, and who can turn it back?” When it says that his hand is stretched out, you should picture a hand raised up getting ready to strike.
Marc Roby: And no one can stand when God strikes, so that should be every bit as frightening to the unbeliever as it is comforting to the Christian.
Dr. Spencer: It should be. In Isaiah 40:6-8, the prophet wrote that “A voice says, ‘Cry out.’ And I said, ‘What shall I cry?’ ‘All men are like grass, and all their glory is like the flowers of the field. The grass withers and the flowers fall, because the breath of the LORD blows on them. Surely the people are grass. The grass withers and the flowers fall, but the word of our God stands forever.’”
Marc Roby: And that, of course, is why we are doing this podcast. Because what the Word of God says does not change and is of eternal importance. Are we finished with looking at God’s immutability?
Dr. Spencer: Not quite, I have one more point to make. God’s immutability is a necessary consequence of his perfection. All change is either change for the better, or for the worse. For example, if your knowledge changes you either learned something new or you forget something. And if your moral purity changes you either become more pure or less pure. Therefore, if God is perfect, and the Bible clearly says that he is, for example in Psalm 18:30 and Matthew 5:48, then you can conclude that he cannot change. Because if he changes, it either means that he wasn’t perfect before and then somehow attained perfection, or he was perfect and now, having changed, he is no longer perfect. James Boice makes a similar argument in his Foundations of the Christian Faith and so does Berkhof in his Systematic Theology.
Marc Roby: That is an example of how all of God’s attributes work together in a consistent and complementary way to describe his being. Are we finished with God’s immutability now?
Dr. Spencer: We are finished with making the biblical case for it, but I want to consider some of the practical ways in which this attribute affects us and also answer some of the objections people raise to it.
Marc Roby: I think that will have to wait for our next session. In closing, let me remind our listeners that they can email their questions or comments to firstname.lastname@example.org. We would appreciate hearing from you.
 Wayne Grudem, Systematic Theology, Inter-Varsity Press, 1994, pg. 231
 All scripture quotations, unless otherwise indicated, are taken from the Holy Bible, New International Version®, NIV® (1984 version). Copyright © 1973, 1978, 1984, 2011 by Biblica, Inc.™ Used by permission of Zondervan. All rights reserved worldwide. www.zondervan.com The “NIV” and “New International Version” are trademarks registered in the United States Patent and Trademark Office by Biblica, Inc.™.
 E.g., see https://www.myjewishlearning.com/article/the-shema/
 James Boice, Foundations of the Christian Faith, Revised in One Volume, InterVarsity Press, 1986, pg. 111
 From the Tarner Lectures, e.g., see https://www.goodreads.com/quotes/213548-the-aim-of-science-is-to-seek-the-simplest-explanations
 William G. T. Shedd, Dogmatic Theology, Charles Scribner’s Sons, 1888, pg. 250
 Wayne Grudem, op. cit., pp 177-180
 In the audio version I reference Isaiah 14:14, which is an error (corrected 4/19/20)
 In the audio version I reference Isaiah 14:115-17, which is an error (corrected 4/19/20)
 Boice, op. cit., pg. 242
 Louis Berkhof, Systematic Theology, Wm. B. Eerdmans Pub. Co., 1938, pg. 58 (This can be purchased as a combination of his Systematic Theology and Introductory Volume to Systematic Theology in one text from Eerdmans, 1996)