This passage occurs in the RCL "Pentecost"/"Ordinary"/"Proper" Season, Year A, most recently October 2017.
Summary: I suppose one could go to great lengths to parse out the Greek meaning of the words, "heart", καρδια, "soul," ψυχη, and "mind," διανοια. After discovering that they mean different things in Greek than in English you learn that Jesus wants us to...drum roll...Love God and love our neighbor with everything we've got. This is probably not much for a sermon, but I find it comforting that Jesus wants us to love God with our minds. In my formation and candidacy, I was often made to feel guilty about my intelligence as if somehow, I just needed to be a big ball of emotions to serve God. One of my professors, Dr. Henrich, pointed out that in this passage, we are called to love God with our mind. This was an incredible word of Gospel to me. Intellection exploration of God's Word is okay too! Funny how law can be heard as Gospel sometimes...
διδασκαλε ("Teacher", 22:36) Thanks be to God Jesus wasn't simply a teacher, but also the savior. However, let us not dismiss the idea of Jesus as teacher. The word teacher appears throughout each Gospel a total of 48 times. What can we learn from Jesus this week?
αγαπαω ("Love" 22:37) One can parse the word love a number of ways. What is interesting here is that αγαπη, which is often thought to refer to divine love, here refers to neighborly love. A reminder that in the kingdom of God, love doesn't remain on heaven, but comes to earth.
καρδια ("heart", 22:37) In Greek, the heart is NOT the center of emotions, but of will.
ψυχη ("soul", 22:37) BDAG points to the broad nature of this word. The soul is, perhaps best said, that which makes flesh alive. The Bible will use the word ψυχη to mean more than simply "the ghostly blue vapor" of our existence. Perhaps another way: our essence? Hard to nail down...
διανοια ("Thoughts" or mind, 22:37): As I stated in my summary, I want to point out that Jesus wants us to love God with our mind. Also interesting is that God admits fulfilling this is impossible. In Genesis 8:21 God says that all our thoughts (διανοια) are bent on evil. Eph 2:3 and 4:18 are similiar. Interestingly, in Jeremiah 31:33, God says he will put the law into our minds. All this points out that not simply our "hearts," but our minds, are also a battle ground for God, a place that needs rebirth. (In fact, this word is often translated from the Hebrew word that means "heart" because the Jewish thought located thoughts in the heart).
χριστος ("annointed" 22:42). This is a very common word in the NT. The reason why I bring it up here is because most of our thoughts about the word "Christ" are not what the listener's in the OT would have heard. They would have expected someone to replace David as a true king over Israel. The spiritualization of his role was a NT development.
Grammatical review: "Hendiadys"
A Hendiadys is a very fancy way of saying "using two words to mean one thing." Literally from the Greek: "One through two." An example of this might be from Genesis 1: "Formless and void." They both essentially mean the same thing. Put them together and you get: "A whole lot of nothing."
In this particular passage, we have a hendiadys typical of the New Testament:
ο νομος και οι προφηται (22:40)
The law and the prophets. This is the NT way of refering to the Old Testament. Sometimes they will include the Psalms, but more often, just these two sections. So Jesus isn't simply saying, "All of the commands and words of the prophets hang on these two commandments" he is saying, "the whole Bible that you know of depends on this."