You know that it was not Abraham who chose God. It was not Abraham who first called upon God, but rather God who called upon Abraham. When he was living in a foreign land with his family, and though his family was worshiping idols, the Lord our God called Abraham to Himself. He called him by name, and He gave him promises. He called him to go to a place that Abraham did not yet know; but he heard and believed the Word of the Lord. By the grace of God, he was a man of faith, indeed, the father of all who believe and trust in the Name of the Lord.
The promises that God gave to Abraham by His grace and mercy, for peace and life, were not only for Abraham, nor only for his own immediate children, nor only for his own descendants after the flesh. But rather, God called Abraham, and blessed Abraham, and gave Abraham promises, and sealed those promises with a Covenant, also for your sake, and for all the nations of the earth. That all might call upon the Name of the Lord, because He has mercy on all who call upon Him.
When God gave Abraham the Covenant of Circumcision, it was to seal with certainty the promise that God had given, the promise that He would fulfill in the flesh and blood of His own Son, born from the family of Abraham in the fullness of time.
What made Abraham faithful and the father of all who believe was the faith in his heart, which was by the Word and Spirit of God. But even aside from Abraham’s faith, there would be given from his own flesh, his own Seed, the Savior, who is Christ Jesus.
And so this Covenant of God with Abraham is given in his very flesh. And it is utterly absurd.
God does such very strange things. That Abraham and his sons, and all of his many sons who would come after him, should have a portion of the skin from their genitals cut off; and this would be God’s Covenant with Abraham and his family! That is very strange. It is painful. It causes embarrassment and shame. It causes blood. And yet, this is God’s Covenant, sealed in flesh and blood, and attached to Abraham’s body, as surely as God’s Word should be held within his heart.
Among Abraham’s descendants there would be those who walked in the faith of their father, and those who did not. But even Abraham himself was not always in all things faithful. Nor Judah. Nor David. Those men of God lived by faith, by the grace of God, but it was God who always remained faithful to them and to His Covenant with them.
So from Abraham’s family there would come the One who fulfilled this Covenant of Circumcision, this Covenant of God’s gracious blessing, His promise that from Abraham would come a Blessing for the nations. It was attached to the flesh of this family, until it should appear in the flesh of God Himself, conceived and born of Mary, and on this Eighth Day circumcised according to the Law.
The Law itself was God’s Covenant with the sons of Abraham, Isaac, and Jacob, with the sons of Israel. For having brought them out of Egypt by His powerful arm and with His outstretched hand, He established His Covenant with them, again with flesh and blood, that is, the blood of bulls and oxen, there at Mt. Sinai. There God appeared to them, and He sealed His Covenant with them with that blood which was sacrificed. Not their own blood in this case, for they were spared, but blood nonetheless. It is by blood that God forgives sins, and with blood that He gives life and salvation.
Thus, with blood He sealed His Covenant with Israel at Sinai, and He gave them His holy and righteous Law to set them apart. As Abraham was set apart, both in his heart and in his body, so was Israel set apart to live by faith and by love. Their lives and relationships would testify to the presence of God among them. For they would be distinct from all the nations of the world. They would worship the Lord in fear, love, and trust. They would hear and heed His Word and call upon His Name. They would be holy and perfect, as the Lord their God is holy and perfect.
So it was that He gave them His Law to discipline their flesh, to show them the way they should live and walk before Him. But in this way, it also exposed and made clear their sins. And it never would be fulfilled in the lives of the people, but only in the Life of Christ, who is God in the flesh, in whom the Law is most surely written and fulfilled and completed. Hence, even in showing them their sins, the Law also described that One who would be their Savior, the One who lives in perfect faith toward God and in perfect love toward both God and man: the Son of God, Christ Jesus.
It is to Christ that the Law has always pointed, and it still does. True, the Ten Commandments per se were given to Israel, as part of God’s Covenant with those ancient people. But those same Ten Commandments summarize the good and gracious will of God, what is His good and acceptable will, also for you. In showing you how to live, His Commandments guide you in the way of faith and love. They point you to your neighbor, that you should serve your neighbor as the Lord your God serves you. And His Ten Commandments are also your tutor, pointing you to Christ Jesus.
A tutor in the ancient world was a trusted household slave who would take the children of the family, the sons of the father, and lead them to and from school, and help them with their lessons, and make sure they learned what they needed to know in order to live, in order to receive and use their father’s inheritance rightly. So the Law serves this purpose for you. It is your tutor. It is not your salvation, but it points to the One who is your Savior. It trains you in the way that you are to go in order to inherit the treasures of your Father in heaven by the faith which is in Christ Jesus.
You are no doubt familiar with the way that we Lutherans have confessed the Ten Commandments, that they function as a mirror, as a curb, and also as a rule or guide for those who are reconciled to God in Christ, for those who are redeemed and righteous by faith. The Ten Commandments are a tutor in this way. They show you how to live. And I suppose that is fairly easy to understand when it comes to loving and serving your neighbor. You are not to hurt or harm your neighbor in his body, his possessions, his family, his income or reputation. Rather, by your words and by your actions, you are to help your neighbor in all of these aspects of life. Help him to protect his body. Help him to keep his stuff, his wife and children. Help to defend his name among his neighbors.
But the first three Commandments also serve as your tutor. And this, not for your neighbor’s benefit, nor for God’s protection, as though you were going to hurt or harm Him. No, the first three Commandments rule and guide and tutor you for your benefit, for your protection. They direct you and even require you to do those things which are for your own good before the Lord.
Those first three Commandments direct you to look to the Lord your God; and in that command there is the certainty that He desires to hear you. They command you to hear His Word, because it is by His Word that He gives you grace and every blessing. It is by His Word that He names you with His own Name. And because He has named you with His own Name, the way in which you speak and the way in which you live are a confession of who your Father is, of who your God is.
So the first three Commandments command you — with all your heart, with all your mind, with your body and your voice — to fear, love, and trust in the one true God above all things. Not because He needs you, but you need Him. He calls you to Himself in love, because He is your Life and your Salvation. It is by faith that you receive all of His gifts. It is in prayer that you call upon Him. And it is with His Word that He serves you and answers all your prayers and all your needs.
His Word, ultimately — from before the foundation of the world, and even into eternity — the Word of the Lord is the Son of God, your Savior, Jesus Christ, whom the Father has given in the flesh and blood of Abraham. He is the Seed of Abraham, the promised One in whom the nations of the world are blessed; in whom you also are blessed through the forgiveness of all your sins.
In Christ Jesus the Covenant that God established with Abraham has been satisfied and fulfilled. And not in some abstract, general sort of way, but this Son of God, Christ Jesus, born of Mary, actually receives in His own flesh, in His own genitals, the Covenant of Circumcision. He bleeds. He hurts. He suffers, already as an Infant, in keeping with the Law of God, which neither Abraham nor any of His other sons or daughters, nor you, could have kept or fulfilled. But Jesus does it all.
Already as an Infant, and into His childhood, and into His manhood; throughout His Life, even unto death, and in His Resurrection from the dead, He has kept the whole entire Law of God. Every jot. Every tittle. Every Commandment, He has kept. And all that you have broken, He has repaired and rectified in His own Body, by His innocent suffering and death upon the Cross, and in His glorious Resurrection. For He has atoned for all of your sins by the shedding of His blood.
In perfect faith and love He has lived. In perfect faith and love He has died. And so it is that, by His Cross and in His Resurrection, He has redeemed you from sin, death, the devil, and hell, and He has reconciled you to the Lord your God in His own Body, in His own flesh and blood.
For this incarnate Son of God, Christ Jesus, is the Lamb. He is the One whom God the Father has provided for Himself in the place of Abraham’s beloved Isaac. He is the Lamb who is given in place of all the sons of Israel, while God humbles Pharaoh under His thumb. He is the Lamb who is given for the sins of the world. He bleeds and dies that you might live. And He feeds you with Himself, with the Passover Feast of His own holy Body and precious Blood, so that you may live.
Not only that, but everything that He has done and accomplished, for you and for all people, has also been given to you by His Word and with His Name in the Sacrament of your Holy Baptism.
St. Paul calls Holy Baptism the Circumcision made without hands. It is the Circumcision of your heart, mind, and spirit. It is the Circumcision worked by the Word and Spirit of the Lord, who cleanses you, who purifies you through the forgiveness of your sins by the blood of Jesus Christ.
In the dying and rising of Holy Baptism, it is not only the Law which disciplines you by the way of the Cross, but all the more so does the Gospel forgive you by the Cross and in the Resurrection of the Lord. So it does by laying Christ upon your heart with the gift and promise of His grace; and not only on your heart, but on your flesh. For the Word of Baptism is combined and included with the water of Baptism that washes over your flesh and cleanses you inside and out. It cleanses your conscience before God, and it cleanses your flesh for the Resurrection unto everlasting Life.
In Holy Baptism, the Name of God which Jesus has received and bears forever in His own Body of human flesh and blood, has been given to you in your flesh. It has been written by His Cross and with His Blood upon your forehead and your heart, upon your body, soul, and spirit. So that, in the Resurrection of your body, you shall be glorious in Christ, and you shall see Him as He is.
You are named by God. And with His Name God has given you Himself. And with Himself He has given you His Life. You belong to Him. You are a child of Abraham by faith in this God. Even better, you are a child of God in Christ Jesus. You are an heir of the Father. You are a son most beloved. Everything He has belongs to you. With His Name He has given you everything.
With His Name, through the forgiveness of all your sins, He has cleansed and purified your heart. He has also cleansed and purified your lips and your life in the flesh, so that you are able by His grace to sing, to pray, and to keep the Feast at all times and in all places, to the glory of His Name, because you belong to Him. You are in Christ Jesus. That is your identity. That is your sonship, be you boy or girl. That is your salvation of body and soul, here in time and hereafter in eternity.
All thanks and praise be unto God through this Savior, Jesus Christ, who has fulfilled God’s holy Law and given you Himself in peace and love, unto the Resurrection and the Life everlasting.
In the Name + of the Father and of the Son and of the Holy Spirit. Amen.