The account of Jesus and Zacchaeus (Luke 19:1-10) is a wonderful revelation of the sovereign grace of Christ in the salvation of sinners. In the context Jesus has told his disciples how hard it is for a rich man to enter the kingdom of God. He demonstrates the impossibility (i.e. human impossibility) by the account of the rich, young ruler. He then turns around, almost immediately, and shows that with God all things are possible," by seeking and saving Zaccheus. Some have suggested that Zacchaeus plays a part in his conversion by climbing up in the sycamore tree "in order to see who Jesus was." But this was  simply because "he could not see who Jesus was, because he was of short stature." Zacchaeus' inability to see Jesus by faith is illustrated by the fact that he is short. By climbing into the tree, he is no closer to Jesus. This only highlights the futile attempts of fallen man. It was not really Zacchaeus seeking Jesus. It was Jesus seeking Zacchaeus.

Jesus walked up to the tree, and said "Zacchaeus, make haste and come down, for  today I must stay at your house." Jesus calls Zacchaeus down--away from his futile efforts to see Christ in his own strength--and then invites Himself into Zacchaeus' house. Note that Zacchaeus did not invite Christ into his house. Jesus invited Himself into Zacchaeus' home. It is, as if he said, "Zacchaeus, I have decided to come to your house. Your house will be My house." It is the Covenant Lord bringing sovereign grace and mercy into the life of  one of His lost sheep. Jesus finishes the interactions by saying, "Today salvation has come to this house, because he also is a son of Abraham; ¹⁰ for the Son of Man has come to seek and to save that which was lost.” Zacchaeus was elect. He was a true son of Abraham. It was not ethinic decent that is mentioned, otherwise Jesus would have had to say the same thing to the rich, young ruler and every other Jew He interacted with. Jesus did not save everyone of Abraham's physical descedants; He came to save all of his spiritual descendants--those chosen with the election of saving grace. Note finally the closing words of this account. Jesus says, "The Son of Man came to seek and save that which was lost." Those who reject sovereign grace in salvation, must reckon with these words. Jesus did not say, "The Son of Man came to seek that which was lost." He came to seek and save the lost. He does all the work for and in them. It is true that Zacchaeus makes the claim, "“Look, Lord, I give half of my goods to the poor; and if I have taken anything from anyone by false accusation, I restore fourfold.” Whether this is another attempt of fallen human pride to self-righteously fix his spiritual blindness, and therefor merit Christ's favor, or not, it is clear that Jesus seeks and saves Zacchaeus for no other reason than the fact that He had chosen him to be one of Abraham's true descendants.