In preparing for a sermon on the Good Samaritan, I came across some classic interpretations which see the parable as pointing to Christ.  Here are selections from three ancient doctors (courtesy of the Ancient Commentary on Scripture), and a 20th century giant:

Ambrose, from his Exposition of the Gospel of Luke, 7.73-84:

Jericho is an image of this world. Adam, cast out from Paradise, that heavenly Jerusalem, descended to it by the mistake of his transgression…He was greatly changed from that Adam who enjoyed eternal blessedness.  When he turned aside to worldly sins, Adam fell among thieves, among whom he would not have fallen if he had not strayed from the heavenly command and made himself vulnerable to them…he received a mortal wound by which the whole human race would have fallen if that Samaritan, on his journey, had not tended to his serious injuries. 7.73]

…Here the Samaritan is going down.  Who is he except he who descended from heaven, who also ascended to heaven the Son of Man who is in heaven?  When he sees half-dead him whom none could cure before, like her with an issue of blood who had spend all her inheritance on physicians, he came near him.  He became a neighbour by acceptance of our common feeling and kin by the gift of mercy.

…”And bound up his wounds, pouring in oil and wine.” That Physician has many remedies with which he is accustomed to cure.  His speech is a remedy.  One of his sayings binds up wounds, another treats with oil, another pours in wine.  He binds wounds with a stricter rule.  He treats with the forgiveness of sins.  He stings with the rebuke of judgment as if with wine.”

Since no one is closer than he who tended to our wounds, let us love him as our neighbour.  Nothing is so close as the head to the members.   Let us also love who is the follower of Christ, let us love him who in unity of body has compassion on another’s need.

Origen, Homilies on the Gospel of Luke, 34.3,9:

One of the elders wanted to interpret the parable as follows.  The man who was going down is Adam.  Jerusalem is paradise, and Jericho is the world. The robbers are hostile powers.  The priest is the law, the Levite is the prophets, and the Samaritan is Christ.  The wounds are disobedience.  The beast is the Lord’s body.  the pandochium (that is, the stable), which accepts all who wish to enter, is the church.  The two denarii mean the Father and the Son.  The manager of the stable is the head of the church, to whom its care has been entrusted.  The fact that the Samaritan promises he will return represents the Saviour’s second coming…

…the Samaritan, “who took pity on the man who have fallen among thieves, is truly a “guardian,” and a closer neighbour than the Law and the Prophets.  He showed that he was the man’s neighbour more by deed than by word.  According to the passage that says, “Be imitators of me, as I too am of Christ,” it is possible for us to imitate Christ and to pity those who “have fallen among thieves.”  We can go to them, bind their wounds, pour in oil and wine, put them on our own animals, and bear their burdens.  The Son of God encourages us to do things like this.  He is speaking not so much to the teacher of the law as to us and to everyone when he says, “Go and do likewise.” If we do, we will receive eternal life in Christ Jesus, to whom is glory and power for ages and ages.

Augustine, Sermon 179A.7-8:

Robbers left you half-dead on the road, but you have been found lying there by the passing and kindly Samaritan. Wine and oil have been poured on you.  You have received the sacrament of the only-begotten Son. You have been lifted onto his mule.  You have believed that Christ became flesh.  You have been brought to the inn, and you are being cured in the church.”That is where and why I am speaking.

…This is what I too, what all of us are doing. we are performing the duties of the innkeeper.  He was told, “If you spend any more, I will pay you when I return.  “If only we spent at least as much as we have received!  However much we spend, borthers and sisters, it is the Lord’s money.

Augustine, Christian Instruction 33:

God our Lord wished to be called our neighbour. The Lord Jesus Christ meant that he was the one who gave help to the man lying half-dead on the road, beaten and left by the robbers. The prophet said in prayer, “As a neighbour and as one’s own borther, so I did please” [cf 1 Cor 6.15]. Since the divine nature is far superior and above our human nature, the command by which we are to love God is distinct from our love of our neighbour.  He shows mercy to us because of his own goodness, while we show mercy to one another because of God’s goodness.  He has compassion on us so that we may enjoy him completely, while we have compassion on another that we may completely enjoy Him.

Karl Barth, Church Dogmatics I/2, III, §18, pp 418-419.

The question with which Jesus concludes the story is which then of the three (i.e., priest, Levite, and Samaritan) proved to be a neighbour to the man who fell among thieves? And the teacher of the Law himself had to reply: “he that showed mercy on him,” i.e., the Samaritan.  This man as such, as the one who showed mercy, is the neighbour about whom the lawyer was asking.  And that is the only point of the story, unequivocally stated by the text.

For the lawyer, who wants to justify himself and therefore does not know who is his neighbour, is confronted not by the poor wounded man with his claim for help, but by the anything but poor Samaritan who makes no claim at all but is simply helpful.

It is the Samaritan who embodies what he wanted to know.  This is the neighbour whom he did not know.   All very unexpected: for the lawyer had first to see that he himself is the man fallen among thieves and lying helpless by the wayside; then he has to note that the others who pass by, the priest and the Levite, the familiar representatives of the dealings of Israel with God, all one after the other do according to the saying of the text: “He saw him and passed by on the other side;” and third, and above all, he has to see that he must be found and treated with compassion by the Samaritan, the foreigner, whom he believes he should hate, as one who hates and is hated by God. He will then know who is his neighbour, and will not ask concerning him as though it were only a matter of the casual clarification of a concept.  He will then know the second commandment, and consequently the first as well.  he will then not wish to justify himself, but will simply love the neighbour, who shows him mercy.  He will then love God, and loving God will inherit eternal life.

…The Good Samaritan, the neighbour who is a helper and will make him a helper, is not far from the lawyer.  The primitive exegesis of the text was fundamentally right.  He stands before him incarnate, although hidden under the form of one whom the lawyer believed he should hate, as the Jews hated the Samaritans.  Jesus does not accuse the man, although judgment obviously hangs over him. Judgment is preceded by grace.  Before this neighbour makes His claim He makes His offer.  Go and do likewise means: Follow thou Me.