Christ in the Old Testament

Genesis 21:12b-13

Listen to whatever Sarah tells you, because it is through Isaac that your offspring will be reckoned. I will make the son of the slave into a nation also, because he is your offspring. (NIV)

Today’s Reading: Genesis 21:1-13, Romans 9:6-9 and Galatians 4:21-31

We are going to explore the symbolic significance of Isaac for at least a couple of days. Remember the promise that God made to Abraham that he would become a great nation and that all peoples on earth would be blessed through him? Well Abraham decided to take matters into his own hands and slept with his servant Hagar because his wife Sarah was barren. That wasn’t God’s plan and to say the least it created some issues.

However God visits Abraham in Genesis 18 and tells him that Sarah will have a son within the next year. Sarah laughs at God which is an amusing exchange recorded between her and Abraham. But God’s word is true and Sarah has a son that she names Isaac which means he laughs. There are a lot of parallels between Isaac and Jesus but for today, let’s look at what Paul had to say about Isaac.

In Paul’s letter to the Romans, he is making the argument that what God meant when he told Abraham that “It is through Isaac that your offspring will be reckoned” was that you aren’t born into the family of God and there’s no way to work yourself into it. You are chosen by God. We can flesh this out a little better by looking at the passage in Galatians.

Paul tells us in his letter to the Galatians that there were two sons born of Abraham. One son was born according to the flesh to the slave Hagar and one son was born by the Spirit (or divine promise) to the free woman Sarah. Both are Abraham’s sons but only one was promised by God and only the offspring of that one will be blessed and be free.

Paul tells us that each son represents the two covenants – the old covenant and the new covenant that we call Testaments. Under the old covenant, you are a slave to the law. You must adhere to all the laws found in the Old Testament and if you fail to obey any of them, you have sinned and you are condemned by the law. There’s nothing you can do to earn your freedom. But under the new covenant, Jesus has paid the price for your sin and once you accept that promise, you become free.

So in this case, we are to become like Isaac. We are children of the promise. There is nothing we can do to earn God’s favor. We must be born again into Christ who was promised by God. It’s a gift that we simply need to receive to become children of God.

Hebrews 11:11 says “By faith Abraham, even though he was too old to have children—and Sarah herself was not able to conceive—was enabled to become a father because he considered him faithful who had made the promise.” And Romans 4:13 says “It was not through the law that Abraham and his offspring received the promise that he would be heir of the world, but through the righteousness that comes by faith.”

Our righteousness and forgiveness comes by faith in Christ just as Isaac was born because of Abraham’s faith in God. Romans 4:19-21 says that Abraham “faced the fact that his body was as good as dead” but “was strengthened in his faith and gave glory to God, being fully persuaded that God had power to do what he had promised.” That’s amazing grace!

Today’s Prayer: Help me have the faith of Abraham and be fully persuaded that you have the power to do what you promise!