Peter Wallace, pastor of Michiana Covenant Presbyterian Church, is very helpful on Luke 18 as well. One of the keys to the passage is understanding that Jesus is not being sarcastic in his answer to the rich young ruler’s question. The man’s question is a good one, and Jesus’ answer is sincere. Wallace writes:
“Why would Jesus say that keeping the commandments is the way to inherit eternal life? Perhaps that is because this is what Moses had said:
You shall walk in all the way that the LORD your God has commanded you, that you may live, and that it may go well with you, and that you may live long in the land that you shall possess. (Dt 5:33)
If you obey the commandments of the LORD your God that I command you today, by loving the LORD your God, by walking in his ways, and by keeping his commandments and his statutes and his rules, then you shall live and multiply and the LORD your God will bless you in the land that you are entering to take possession of it. (Dt 30:16)
Israel was the son of God (Exodus 4:22-23). As the son of God, Israel was called to imitate his father.
And this rich ruler is an Israelite. He is one of the covenant people of God. And Jesus addresses him as such.
Notice that Jesus makes it clear that the demand of the law upon Israel was not perfection: No one is good except God alone. Moses and Jesus agree that Israel cannot perfectly keep the law (that is why God gave Israel all those sacrifices, in order to deal with sin!) But the law is given as the rule of life and conduct for the people of God. And so if you, as God’s child, would inherit eternal life, then keep his commandments!”
Jesus is affirming the way of the covenant of grace in the Old Testament, but with this addition, now that Israel’s Messiah has come: the one who would inherit eternal life – the age to come, the way of the kingdom – must follow Jesus.
This isn’t really the main point for Luke 18, but in the context of current discussions about the alleged republication of the covenant of works in the Mosaic covenant, I really have to point out the simple clarity of Peter Wallace in that last paragraph:
“Moses and Jesus agree that Israel cannot perfectly keep the law (that is why God gave Israel all those sacrifices, in order to deal with sin!)”
Moses and Jesus agree. Exactly.