January 1st is the commemoration of the circumcision of our Lord. Here’s the Holy Gospel for that day, the Gospel according to Luke 2:21: “And at the end of eight days, when he was circumcised, he was called Jesus, the name given by the angel before he was conceived in the womb.”
Luther began his first sermon on this event with these words: “This is a short Gospel lesson, and we’ll make a short ‘sermon’ out of it.” He then preached a ten page sermon. I like that, so let me just say, “This is a short gospel lesson, and we’ll make a short ‘devotion’ out of it.”
You might not want Luther as a euchre partner, though. He reneged a few pages later, “That’s why the observance of Christ’s circumcision offers such a rich sermon; there’s enough here to talk about for several hours!” I imagine some of his hearers might have squirmed, and they were used to longer sermons than we are.
How could Luther say that it contained hours of preachment? But then I read this gem:
One lesson we can learn from the old circumcision is this: when God wants to help his people, he sometimes does it in ways that are nothing less than ridiculous as far as human judgment is concerned! … This became so offensive to the Gentiles that they responded with all sorts of spiteful and scoffing nicknames for the Jews! ... That’s how all God’s commandments fare: reason butts its head against them and takes offense.” 
Let’s go back in time a bit to the start of the whole circumcision thing, Genesis 17:
God said to Abraham, “This is my covenant, which you shall keep, between me and you and your offspring after you: Every male among you shall be circumcised. You shall be circumcised in the flesh of your foreskins, and it shall be a sign of the covenant between me and you. He who is eight days old among you shall be circumcised. Every male throughout your generations, whether born in your house or bought with your money from any foreigner who is not of your offspring, both he who is born in your house and he who is bought with your money, shall surely be circumcised. So shall my covenant be in your flesh an everlasting covenant. Any uncircumcised male who is not circumcised in the flesh of his foreskin shall be cut off from his people; he has broken my covenant.” (Gen. 17: 9-14).
Let’s be honest here, gentlemen. Who of us, had we been Abraham, wouldn’t have had at least a few questions before fetching the flint knife? “Are you sure, God? Perhaps there is another way? Why?” And again, “Are you sure, God? Perhaps there is another way? Why?” But we find no questions. Just faith and a flint knife.
Remember, this is Genesis 17. Isaac is born in Genesis 21. The promise to the patriarchs, like the promise to Adam and Eve, was one of offspring. “Through your Seed, blessing” is the refrain of the Old Testament. The glory of Israel and the light of the Gentiles hung on a family tree. And so Israelite men and their wives were constantly reminded of the promise of God as it was intimately marked upon their relationship as a sign and seal. It may have seemed foolish, but on Christmas day the four finished off the two plus two. It clicked and all that was left was to say, “Amen.”
Through your Seed, blessing” is the refrain of the Old Testament
God has a way of working wondrous things through foolish means. When you see water poured on a child’s head and hear the pastor say, “You are a redeemed child of God,” speak “Amen.” When you have bread and wine placed into your mouth by the pastor and hear him say, “The body and blood of Christ,” speak “Amen.” When you, knowing your wretched condition, confess to your pastor and hear him say, “I forgive you in the name of the Father and of the Son (+) and of the Holy Spirit,” speak “Amen.” When you suffer loss and the Bible assures you that all things work for good for those whom God has called, who love him, speak “Amen.” When you experience gain and the Bible warns you that these blessings are not the fruit of your own hands but the blessing of God Almighty, speak “Amen.” It may not all make sense at the time, but the four is following the two plus two, as Christ followed circumcision. Sometimes only an “Amen” will do.
Who knew the circumcision of our Lord had so much to teach us? Apparently, Luther did. Hopefully now we do, too. Christ has received the mark of law that we might be marked with the gospel, with the sign of his holy cross on our heads and hearts as redeemed children of God. Already here, in his infancy, Christ sheds blood on our behalf. On this day the fulfillment of the promise received the sign of the covenant, the one-way covenant God established with Abraham regarding the coming Messiah, and he did so, as he did everything, for us.
Christ is circumcised. You’re baptized. God is well-pleased with it all, for he has arranged it, and, through Christ, he is well-pleased with you. It is ridiculous, all of it, but that’s the beauty of it all. It’s the kind of thing to which one can only speak an “Amen.” This might seem a ridiculous commemoration at first, but it nevertheless makes for more than the short sermon we might expect.