The true sons of Abraham all have salvation, because they all have the faith of Abraham. Abraham had many descendants, but most of them were only his descendants according go the flesh.
What a picture of the grace of God this is! We would have found Zacchaeus a most unattractive individual. Why did God fix on him? Why did the Lord Jesus determine to have him come down, and to change him and to save him? To teach us this, that salvation is sheer grace. Thank God it is, because there is a sense in which every one of us can claim to be the worst in the sight of God. Nobody can be converted and have an encounter with God, until they begin to respect and reverence him, and realize that he is the holy God of the heavens. Equally nobody can have a conversion, nobody can seek God, until they really do realize their own moral weakness. You won't seek the Lord until you feel it, until you realize how rotten you are within. What a picture of mercy and grace, so surprising.
What comes out from the conversion of Zacchaeus? The fact that salvation is absolutely personal. The preacher preaches to a gathering of people, but the Lord, who alone can convert, will deal with them one by one. Can you imagine the astonishment and surprise of Zacchaeus to hear his name called? How did Jesus know his name? He was used to interviewing people, but he wasn't used to being interviewed. These tax inspector types never are. He was the one who sat behind a high desk with a henchman on either side. He was the one who conducted the inquisition to find out how much people owed him. But here, the Lord Jesus Christ, with his majesty and authority, calls him by name and calls him to account. That is salvation. We begin to revere God, we begin to feel our own unworthiness, and we begin to seek the Lord at a very personal level. How can I be saved? How can I be converted? By developing a great reverence for Almighty God who I've spurned. By coming to see my need and my rottenness, my vanity of life. By seeking the Lord Jesus personally.
Another thing we notice is this: the Lord Jesus Christ not only deals with Zacchaeus personally, but with such affection. He calls him a son of Abraham. He meets with him. He goes to his house. He is entertained by him. The affection of the Lord Jesus Christ, what a theme for us. If there is somebody who is not yet converted, and you seek to repent of your sins, and you plead with God to change your life and to convert you, if you are in earnest you will taste the affection of Almighty God. You will learn something about the love of the Lord Jesus. You will be seeking the one who is so full of love for those whom he saves, that he was willing to come down out of heaven and suffer and die on Calvary to bear the punishment for your sins. You will be dealing with one who is so full of love and affection that in order to deliver you from being judged and cast away for all eternity, he would willingly take the pain and the punishment of your sin himself.