Luke 15:11 says, “And he said, ‘There was a man who had two sons.’”
Jesus, here, was adding another parable to the two He had just spoken, about the same topic. He was setting forth the differences in character of the Scribes and Pharisees and the tax collectors and sinners.
The “man” mentioned in verse 11 is God the Father. God is in fact not a man, nor should an image of Him be created as a man, but inasmuch as men are created in His image, He is sometimes compared to a man and thus, in other places of Scripture, is called “man of war” or “husbandman“, etc. This imagery doesn’t contradict with the reality that He is spirit. Only the second person of the Trinity assumed a human nature, and therefore, whenever God is referred to as a man, Jesus is almost always the subject. But even though God the Father never took on human form, here in this parable, it seems that it is He who is represented as the man in verse 11.
Why? The character of a father and having sons more properly belongs to Him. Also, the reception of sinners and the forgiveness of their sins through Jesus Christ agree with Him. Also, as we’ll see, Christ is distinguished from the Father by other things in this parable.
The “two sons” in verse 11 are not angels and men, angels being the older brother and men being the younger, even though angels are otherwise called the sons of God and are older than men in terms of creation. And even though the elect angels have been serving God for eons and have never sinned against Him, they are never called brothers of men. Furthermore, they are never angry at the return and the reception of a lost sinner. The opposite is true of the older brother.
Neither is verse 11 making reference to Jews and Gentiles, which is a common interpretive error that students of the Bible make. Those who make this error suppose that the older brother is the Jewish nation, and it partly makes sense, given their external privileges, being God’s covenant people. And the character of the older brother greatly agreed with that of the majority of the nation in Jesus’s time. And it is certain that they did indeed resent the Gentiles. Those who understand this passage like this suppose that the younger brother is the Gentiles who were proselyted into Christianity. However, the gospel had not yet been preached to the Gentiles, nor were they yet brought to repentance. Nor had the Jews yet grumbled against God’s grace to the Gentiles.
In this context, the two sons in verse 11 are the Scribes and Pharisees (the older brother) and the tax collectors and sinners (the younger brother). The same is meant by the two sons in Matthew 21:28. Jews were considered the sons of God by natural adoption, and the Pharisees considered themselves children of God, favorites of heaven, special. But God’s elect among them, including some of the tax collectors and sinners, were truly sons of God. These were predestined as His sons (Ephesians 1:5).
Christian, the grace that will be bestowed on this younger son in this parable applies to you. We are completely undeserving of God’s favor. In fact, we deserve nothing but His wrath. Yet He has called us His sons and has given us a royal inheritance. There is so much more grace and mercy that will be expressed in the rest of this passage, but in this moment, dwell in the amazing thought that we, wretched sinners, are considered true children of God.