A cornerstone belief of the Christian faith, the doctrine of the Trinity distinguishes Christianity from all other faiths. This doctrine makes possible the redemption of sinful human beings and God’s eventual eradication of evil and suffering. Also, a trinitarian God enhances the free will capability of redeemed humans to experience and express his love. Due to its weighty implications, helping people of other faiths see the Trinity in texts they accept as sacred is a worthwhile endeavor.

What is the doctrine of the Trinity? Christian scholars have written many thick books answering this question.1 In chapter 9 of my book, Beyond the Cosmos, I briefly define the Trinity within four pages.2 Here, I will reduce it to one long sentence: There is only one God, but in the unity of the Godhead there are three eternal, coequal Persons where each Person is independently conscious and self-directing but never acting independently of one another and always manifesting the same character attributes and the same nature.

Where in the Bible is the Trinity taught? As I demonstrated in Beyond the Cosmos, the doctrine of the Trinity is expressed in 38 of the Bible’s 66 books. It is taught in 25 of the 27 books of the New Testament and in 13 of the 39 books of the Old Testament.

Which book of the Bible provides the most extensive and detailed teaching on the Trinity? Jews and Muslims believe that there are only scant and ambiguous references to the Trinity in the Old Testament and that Christians base their doctrine of the Trinity on New Testament texts. Many Christians, in fact, do. However, as much as the New Testament expounds on the doctrine of the Trinity, there is an Old Testament book that has more to say about the Trinity than the Gospel of John and Revelation combined—the two New Testament books that say the most about the Trinity. That Old Testament book is Isaiah.

Over the last few decades I have challenged many skeptics of trinitarian doctrine to read through the book of Isaiah in one sitting. Consequently, I have seen many of them, including Jews and Muslims, become convinced of the truth of the Trinity. I have seen even greater success when I have collected for skeptics in a single document everything Isaiah states that is relevant to the Trinity. I want this tool to be used as widely as possible; thus, I present the document here where it will be permanently available for online linking.

I have used the 2017 edition of the Christian Standard Bible throughout this list of Isaiah passages. The reason for my translation choice is that many Jews and other skeptics of the Trinity believe that the only Hebrew word that indisputably and consistently refers to God is the tetragrammaton YHWH (Yahweh). The Christian Standard Bible always translates YHWH as Lord, where “L” is a big capital letter followed by “ord” in small capital letters. Since WordPress (in which this document is written) does not permit the use of small capital letters, in the following passages I have used bold lettering for every instance where Lord is translated from YHWH. Isaiah repeatedly declares that YHWH is one and there is no other God and yet each member of the triune Godhead is referred to as YHWH. I trust that seeing copious specific references to different aspects of the triune God will bear fruitful discussion and lead to persuasion.

Isaiah Passages on the Trinity
Isaiah 1:4 They have abandoned the Lord; they have despised the Holy One of Israel; they have turned their backs on him.

Isaiah 2:3–4 Many peoples will come and say, “Come, let us go up to the mountain of the Lord, to the house of the God of Jacob. He will teach us about his ways so that we may walk in his paths.” For instruction will go out of Zion and the word of the Lord from Jerusalem. He will settle disputes among the nations and provide arbitration for many peoples.

Isaiah 4:2 On that day the Branch of the Lord will be beautiful and glorious, and the fruit of the land will be the pride and glory of Israel’s survivors.

Isaiah 6:5 My eyes have seen the King, the Lord of Armies. [context: Isaiah 6:1–5]

Isaiah 6:8 I heard the voice of the Lord asking: Who will I send? Who will go for us?

Isaiah 7:14 Therefore, the Lord himself will give you a sign: See the virgin will conceive, have a son, and name him Immanuel [God with us].

Isaiah 8:13–14 You are to regard only the Lord of Armies as holy. Only he should be feared; only he should be held in awe. He will be a sanctuary; but for the two houses of Israel, he will be a stone to stumble over and a rock to trip over.

Isaiah 9:6–7 For a child will be born for us, a son will be given to us, and the government will be on his shoulders. He will be named Wonderful Counselor, Mighty God, Eternal Father, Prince of Peace. The dominion will be vast, and its prosperity will never end. He will reign on the throne of David and over his kingdom, to establish and sustain it with justice and righteousness from now on and forever. The zeal of the Lord of Armies will accomplish this.

Isaiah 10:17 Israel’s Light will become a fire, and its Holy One a flame.

Isaiah 11:1–3 Then a shoot will grow from the stump of Jesse, and a branch from his roots will bear fruit. The Spirit of the Lord will rest on him—the Spirit of wisdom and understanding, the Spirit of counsel and strength, a Spirit of knowledge and of the fear of the Lord. His delight will be in the fear of the Lord. [context: Isaiah 11:1–16]

Isaiah 12:2 Indeed, God is my salvation; I will trust him and not be afraid, for the Lord, the Lord himself, is my strength and my song. He has become my salvation.

Isaiah 16:5 a throne will be established in love, and one will sit on it faithfully in the tent of David, judging and pursuing what is right, and quick to execute justice.

Isaiah 17:7, 10 On that day people will look to their Maker and will turn their eyes to the Holy One of Israel. . . . For you have forgotten the God of your salvation, and you have failed to remember the rock of your strength.

Isaiah 19:19–20 On that day there will be altar to the Lord in the center of the land of Egypt and a pillar to the Lord near her border. It will be a sign and witness to the Lord of Armies in the land of Egypt. When they cry out to the Lord because of their oppressors, he will send them a savior and leader, and he will rescue them.

Isaiah 22:21–25 He will be a father to the inhabitants of Jerusalem and to the house of Judah. I will place the key of the house of David on his shoulder; what he opens, no one can close; what he closes, no one can open. I will drive him, like a peg, into a firm place. He will be a throne of honor for his father’s family. They will hang on him all the glory of his father’s family: the descendants and the offshoots—all the small vessels, from bowls to every kind of jar. “On that day,”—the declaration of the Lord of Armies—“the peg that was driven into a firm place will give way, be cut off, and fall, and the load on it will be destroyed.” Indeed, the Lord has spoken.

Isaiah 24:15–16 Therefore, in the east honor the Lord! In the coasts and islands of the west honor the name of the Lord, the God of Israel. From the ends of the earth we hear songs: The Splendor of the Righteous One.

Isaiah 25:8–9 When he has swallowed up death once and for all, the Lord will wipe away the tears from every face and remove his people’s disgrace from the whole, for the Lord has spoken. On that day it will be said, “Look, this is our God; we have waited for him, and he has saved us. This is the Lord; we have waited for him. Let’s rejoice and be glad in his salvation.”

Isaiah 26: 4, 7 Trust in the Lord forever, because in the Lord, the Lord himself, is an everlasting rock! The path of the righteous is level; you clear a straight path for the righteous.

Isaiah 26:13 Lord our God, lords other than you have owned us, but we remember your name alone.

Isaiah 28:16 Therefore the Lord says: “Look, I have laid a stone in Zion, a tested stone, a precious cornerstone, a sure foundation; the one who believes will be unshakable.”

Isaiah 28:21 For the Lord will rise up as he did at Mount Perazim. He will rise in wrath, as at the Valley of Gibeon, to do his work, his unexpected work, and to perform his task, his unfamiliar task.

Isaiah 28:26 His God teaches him order; he instructs him.

Isaiah 32:15 . . . until the Spirit from on high is poured out on us. Then the desert will become an orchard, and the orchard will seem like a forest.

Isaiah 33:2 Lord, be gracious to us! We wait for you. Be our strength every morning and our salvation in time of trouble.

Isaiah 33:17 Your eyes will see the King in his beauty; you will see a vast land.

Isaiah 33:22 For the Lord is our Judge, the Lord is our Lawgiver, the Lord is our King. He will save us.

Isaiah 35:2, 4 They will see the glory of the Lord, the splendor of our God. . . . Say to the cowardly: “Be strong: do not fear! Here is your God; vengeance is coming. God’s retribution is coming; he will save you.”

Isaiah 40:3–5 Prepare the way of the Lord in the wilderness; make a straight highway for our God in the desert. Every valley will be lifted up, and every mountain and hill will be leveled; the uneven ground will become smooth and the rough places a plain. And the glory of the Lord will appear, and all humanity together will see it, for the mouth of the Lord has spoken.

Isaiah 40:9–11 Say to the cities of Judah, “Here is your God!” See, the Lord comes with strength, and his power establishes his rule. His wages are with him, and his reward accompanies him. He protects his flock like a shepherd; he gathers the lambs in his arms and carries them in the fold of his garment. He gently leads those that are nursing.

Isaiah 40:13–14 Who has directed the Spirit of the Lord, or who gave him counsel? Who did he consult? Who gave him understanding and taught him the paths of justice? Who taught him knowledge and showed him the way of understanding?

Isaiah 40:25 “To whom will you compare me, or who is my equal?” asks the Holy One.

Isaiah 41:14 “Do not fear, you worm Jacob, you men of Israel. I will help you”—this is the Lord’s declaration. Your Redeemer is the Holy One of Israel.

Isaiah 42:1–4 “This is my servant; I strengthen him, this is my chosen one; I delight in him, I have put my Spirit on him; he will bring justice to the nations. He will not cry out or shout or make his voice heard in the streets. He will not break a bruised reed, and he will not put out a smoldering wick; he will faithfully bring justice. He will not grow weak or be discouraged until he has established justice on earth. The coasts and islands will wait for his instruction.”

Isaiah 42:6–7 I am the Lord. I have called you for a righteous purpose, and I will hold you by your hand. I will watch over you, and I will appoint you to be a covenant for the people and a light to the nations, in order to open blind eyes, to bring out prisoners from the dungeon, and those sitting in darkness from the prison house.

Isaiah 42:19 Who is blind but my servant, or deaf like my messenger I am sending? Who is blind like my dedicated one, or blind like the servant of the Lord?

Isaiah 43:3 For I am the Lord your God, the Holy One of Israel, and your Savior.

Isaiah 43:10–11 “You are my witnesses,”—this is the Lord’s declaration—“and my servant whom I have chosen, so that you may know and believe me and understand that I am he. No god was formed before me, and will there be none after me. I—I, am the Lord. Besides me, there is no savior.

Isaiah 43:14 This is what the Lord, your Redeemer, the Holy One of Israel says.

Isaiah 44:3 For I will pour water on the thirsty land and streams on the dry ground; I will pour out my Spirit on your descendants and my blessing on your offspring.

Isaiah 44:6 Thus says the Lord, the King of Israel and his Redeemer, the Lord of hosts: “I am the first and I am the last, and there is no God besides Me.” (NASB)

Isaiah 44:24 This is what the Lord, your Redeemer who formed you from the womb, says: “I am the Lord, who made everything; who stretched out the heavens by myself; who alone spread out the earth;”

Isaiah 45:5 “I am the Lord, and there is no other; there is no God but me.”

Isaiah 45:6 “I am the Lord, and there is no other.”

Isaiah 45:14–15 They will confess to you, “God is indeed with you, and there is no other; there is no other God.” Yes, you are a God who hides, God of Israel, Savior.

Isaiah 45:18 “I am the Lord, and there is no other.”

Isaiah 45:21 “There is no other God but me, a righteous God and Savior; there is no one except me.”

Isaiah 45:24 “Righteousness and strength are found only in the Lord.”

Isaiah 46:9 “I am God, and there is no other; I am God, and no one is like me”

Isaiah 47:4 The Holy One of Israel is our Redeemer; The Lord of Armies is his name.

Isaiah 48:12 “I am he; I am the first, I am also the last.”

Isaiah 48:16–17 And now the Lord God has sent me and his Spirit. This is what the Lord, your Redeemer, the Holy One of Israel says: “I am the Lord your God.”

Isaiah 49:4–9 Yet my vindication is with the Lord, and my reward is with my God. And now, says the Lord, who formed me from the womb to be his servant, to bring Jacob back to him so that Israel might be gathered to him; for I am honored in the sight of the Lord, and my God is my strength—he says, “It is not enough for you to be my servant raising up the tribes of Jacob and restoring the protected one of Israel. I will also make you a light for the nations, to be my salvation to the ends of the earth.” This is what the Lord, the Redeemer of Israel, his Holy One, says to one who is despised, to one abhorred by the people, to a servant of rulers: “Kings will see, princes will stand up, and they will bow down because of the Lord, who is faithful, the Holy One of Israel—and he has chosen you.” This is what the Lord says: “I will answer you in a time of favor, and I will help you in the day of salvation. I will keep you, and I will appoint you to be a covenant for the people, to restore the land, to make them possess the desolate inheritances, saying to the prisoners, ‘Come out,’ and to those who are in darkness, ‘Show yourselves.’”

Isaiah 49:26 “I, the Lord, am your Savior, and your Redeemer, the Mighty One of Jacob.”

Isaiah 50:4–9 The Lord has given me the tongue of those who are instructed to know how to sustain the weary with a word. He awakens me each morning; he awakens my ear to listen like those being instructed. The Lord God has opened my ear, and I was not rebellious; I did not turn back. I gave my back to those who beat me, and my cheeks to those who tore out my beard. I did not hide my face from scorn and spitting. The Lord will help me; therefore I have not been humiliated; therefore I have set my face like flint, and I know I will not be put to shame. The one who vindicates me is near; who will contend with me? Let us confront each other. Who has a case against me? Let him come near me! In truth, the Lord God will help me; who will condemn me? Indeed, all of them will wear out like a garment; a moth will devour them.

Isaiah 52:13–53:12 See, my servant will be successful; he will be raised and lifted up and greatly exalted. Just as many were appalled at you—his appearance was so disfigured that he did not look like a man, and his form did not resemble a human being—so he will sprinkle many nations. Kings will shut their mouths because of him, for they will see what had not been told them, and they will understand what they had not heard.

Who has believed what we have heard? And to whom has the arm of the Lord been revealed? He grew up before him like a young plant and like a root out of dry ground.
He didn’t have an impressive form or majesty that we should look at him, no appearance that we should desire him. He was despised and rejected by men, a man of suffering who knew what sickness was. He was like someone people turned away from; he was despised, and we didn’t value him. Yet he himself bore our sicknesses,
and he carried our pains; but we in turn regarded him stricken, struck down by God, and afflicted. But he was pierced because of our rebellion, crushed because of our iniquities; punishment for our peace was on him, and we are healed by his wounds.

We all went astray like sheep; we all have turned to our own way; and the Lord has punished him for the iniquity of us all. He was oppressed and afflicted, yet he did not open his mouth. Like a lamb led to the slaughter and like a sheep silent before her shearers, he did not open his mouth. He was taken away because of oppression and judgment, and who considered his fate? For he was cut off from the land of the living; he was struck because of my people’s rebellion. He was assigned a grave with the wicked, but he was with a rich man at his death, because he had done no violence
and had not spoken deceitfully.

Yet the Lord was pleased to crush him severely. When you make him a guilt offering, he will see his seed, he will prolong his days, and by his hand, the Lord’s pleasure will be accomplished. After his anguish, he will see light and be satisfied. By his knowledge, my righteous servant will justify many, and he will carry their iniquities. Therefore I will give him the many as a portion, and he will receive the mighty as spoil, because he willingly submitted to death, and was counted among the rebels; yet he bore the sin of many and interceded for the rebels.

Isaiah 54:5 Indeed, your husband is your Maker—his name is the Lord of Armies—and the Holy One of Israel is your Redeemer; he is called the God of the whole earth.

Isaiah 55:3–4 I will make a permanent covenant with you on the basis of the faithful kindnesses of David. Since I have made him a witness to the peoples, a leader and commander for the peoples.

Isaiah 59:16 He saw that there was no man—he was amazed that there was no one interceding; so his own arm brought salvation, and his own righteousness supported him.

Isaiah 59:19–20 They will fear the name of the Lord in the west and his glory in the east, for he will come like a rushing stream driven by the wind of the Lord. “The Redeemer will come to Zion, and to those in Jacob who turn from transgression.” This is the Lord’s declaration.

Isaiah 60:9 Yes, the coasts and island will wait for me with the ships of Tarshish in the lead, to bring your children from far away, their silver and gold with them, for the honor of the Lord your God, the Holy One of Israel, who has glorified you.

Isaiah 60:16 You will nurse on the milk of nations, and nurse at the breast of kings; you will know that I, the Lord, am your Savior and Redeemer, the Mighty One of Jacob.

Isaiah 61:1–3 The Spirit of the Lord God is on me, because the Lord has anointed me to bring good news to the poor. He has sent me to heal the brokenhearted, to proclaim liberty to the captives and freedom to the prisoners, to proclaim the year of the Lord’s favor and the day of our God’s vengeance, to comfort all who mourn, to provide for those who mourn in Zion; to give them a crown of beauty instead of ashes, festive oil instead of mourning, and splendid clothes instead of despair.

Isaiah 62:11–12 Look, the Lord has proclaimed to the ends of the earth, “Say to Daughter Zion: Look, your salvation is coming, his wages are with him, and his reward accompanies him.” And they will be called the Holy People, the Lord’s Redeemed; and you will be called Cared For, A City Not Deserted.

Isaiah 63:8–11 He said, “They are indeed my people, children who will not be disloyal,” and he became their Savior. In all their suffering, he suffered, and the angel of his presence saved them. He redeemed them because of his love and compassion; he lifted them up and carried them all the days of the past. But they rebelled and grieved his Holy Spirit. So he became their enemy and fought against them. Then he remembered the days of the past, the days of Moses and his people. Where is he who brought them out of the sea with the shepherds of his flock? Where is he who put his Holy Spirit among the flock?

Isaiah 63:14–16 Like cattle that go down into the valley, the Spirit of the Lord gave them rest. You led your people this way to make a glorious name for yourself. Look down from heaven and see from your lofty home—holy and beautiful. Where is your zeal and your might? Your yearning and your compassion are withheld from me. Yet you are our Father, even though Abraham does not know us and Israel doesn’t recognize us. You, Lord, are our Father; your name is Our Redeemer from Ancient Times.