In May, we studied Exodus 12:1–14, which introduced the idea of substitution: In order to escape the destroyer, who would kill the firstborn male of every family as a judgment on Egypt, an unblemished male lamb had to be killed and its blood sprinkled on the lintels and doorposts of Israelite houses. The Passover lamb was a substitute for the firstborn males of Israel, and St. Paul makes the connection with Jesus explicit when he says, “Christ, our Passover lamb, has been sacrificed” (1 Corinthians 5:7). Later in the same Epistle, St. Paul emphasizes the substitutionary work of Jesus, teaching that it was “of first importance … that Christ died for our sins in accordance with the Scriptures” (1 Corinthians 15:3). In addition to the Passover lamb, there are other substitutes in the Old Testament that point to the person and work of Jesus Christ. These will be the subject of this study.
Rev. Carl Roth, pastor of Grace Lutheran Church in Elgin, TX, joins Sarah to talk about the “Searching Scripture” feature in the August 2025 issue of the Lutheran Witness titled “Substitutes” on Genesis 17:15–21 and 22:1–18. This year, “Searching Scripture” is themed “Opening the Old Testament” and will walk through ways that the Old Testament witnesses to Jesus Christ and His grace, mercy and peace, delivered through the holy Christian church. Follow along every month and search Scripture with us!
Find online exclusives of the Lutheran Witness at witness.lcms.org and subscribe to the Lutheran Witness at cph.org/witness.
Genesis 17:15–21
Isaac’s Birth Promised
15 And God said to Abraham, “As for Sarai your wife, you shall not call her name Sarai, but Sarah[a] shall be her name. 16 I will bless her, and moreover, I will give[b] you a son by her. I will bless her, and she shall become nations; kings of peoples shall come from her.” 17 Then Abraham fell on his face and laughed and said to himself, “Shall a child be born to a man who is a hundred years old? Shall Sarah, who is ninety years old, bear a child?” 18 And Abraham said to God, “Oh that Ishmael might live before you!” 19 God said, “No, but Sarah your wife shall bear you a son, and you shall call his name Isaac.[c] I will establish my covenant with him as an everlasting covenant for his offspring after him. 20 As for Ishmael, I have heard you; behold, I have blessed him and will make him fruitful and multiply him greatly. He shall father twelve princes, and I will make him into a great nation. 21 But I will establish my covenant with Isaac, whom Sarah shall bear to you at this time next year.”
Footnotes
- Genesis 17:15 Sarai and Sarah mean princess
- Genesis 17:16 Hebrew have given
- Genesis 17:19 Isaac means he laughs
Genesis 22:1–18
The Sacrifice of Isaac
22 After these things God tested Abraham and said to him, “Abraham!” And he said, “Here I am.” 2 He said, “Take your son, your only son Isaac, whom you love, and go to the land of Moriah, and offer him there as a burnt offering on one of the mountains of which I shall tell you.” 3 So Abraham rose early in the morning, saddled his donkey, and took two of his young men with him, and his son Isaac. And he cut the wood for the burnt offering and arose and went to the place of which God had told him. 4 On the third day Abraham lifted up his eyes and saw the place from afar. 5 Then Abraham said to his young men, “Stay here with the donkey; I and the boy[a] will go over there and worship and come again to you.” 6 And Abraham took the wood of the burnt offering and laid it on Isaac his son. And he took in his hand the fire and the knife. So they went both of them together. 7 And Isaac said to his father Abraham, “My father!” And he said, “Here I am, my son.” He said, “Behold, the fire and the wood, but where is the lamb for a burnt offering?” 8 Abraham said, “God will provide for himself the lamb for a burnt offering, my son.” So they went both of them together.
9 When they came to the place of which God had told him, Abraham built the altar there and laid the wood in order and bound Isaac his son and laid him on the altar, on top of the wood. 10 Then Abraham reached out his hand and took the knife to slaughter his son. 11 But the angel of the Lord called to him from heaven and said, “Abraham, Abraham!” And he said, “Here I am.” 12 He said, “Do not lay your hand on the boy or do anything to him, for now I know that you fear God, seeing you have not withheld your son, your only son, from me.” 13 And Abraham lifted up his eyes and looked, and behold, behind him was a ram, caught in a thicket by his horns. And Abraham went and took the ram and offered it up as a burnt offering instead of his son. 14 So Abraham called the name of that place, “The Lord will provide”;[b] as it is said to this day, “On the mount of the Lord it shall be provided.”[c]
15 And the angel of the Lord called to Abraham a second time from heaven 16 and said, “By myself I have sworn, declares the Lord, because you have done this and have not withheld your son, your only son, 17 I will surely bless you, and I will surely multiply your offspring as the stars of heaven and as the sand that is on the seashore. And your offspring shall possess the gate of his[d] enemies, 18 and in your offspring shall all the nations of the earth be blessed, because you have obeyed my voice.”
Footnotes
- Genesis 22:5 Or young man; also verse 12
- Genesis 22:14 Or will see
- Genesis 22:14 Or he will be seen
- Genesis 22:17 Or their
English Standard Version (ESV) The Holy Bible, English Standard Version. ESV® Text Edition: 2016. Copyright © 2001 by Crossway Bibles, a publishing ministry of Good News Publishers. esv.org
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Today’s episode of The Coffee Hour is underwritten in part by Concordia, Nebraska. You can learn more about Concordia, Nebraska at cune.edu.

