Biblical Anthropology: Part I

What does the Bible have to say about humanity?  More specifically, what does the Bible have to say about the makeup of humans?  Are humans a basic unity, indivisible?  Or are humans made up of different parts?  I have been interested for some time now with this question because I think how one answers the previous questions has tremendous influence on how one leads one's life.

Let me take as a jumping off point, a couple of verses from the Old and New Testaments that might speak to this issue.

First is the Shema and its later use in New Testament citations.

Deut. 6:5 You shall love the LORD your God with all your heart, and with all your soul, and with all your might.

Mark then quotes from this verse as follows:

Mark 12:30 you shall love the Lord your God with all your heart, and with all your soul, and with all your mind, and with all your strength.

Notice how, to Deuteronomy's heart, soul and might, Mark has added "mind" as well.  Luke follows Mark in his translation, but Matthew quotes Deuteronomy as follows:

Matt. 22:37 He said to him, “‘You shall love the Lord your God with all your heart, and with all your soul, and with all your mind.

Matthew has removed "strength/might" altogether and substituted "mind."

So, do these verses talk about different "parts" of humanity, parts that could be separated?  Is the heart a discreet "part" of the human?  Obviously not in the sense of the heart in modern science as an organ.  Yet, the heart as the seat of the emotions, is that a "part" of the human that can be separated from the other parts?  Can it exist on its own?  What about the soul?

Let's look at one more verse. I Thessalonians also talks about different "parts" of the human as follows:

1Th. 5:23  May the God of peace himself sanctify you entirely; and may your spirit and soul and body be kept sound and blameless at the coming of our Lord Jesus Christ.

 Here we have three "parts" of the human: spirit, soul, and body.  Can they be separated?  I think that in modern evangelical Christianity, humanity is usually represented along the lines of these three "parts": Body, Soul, and Spirit.  See the picture to the left which comes from a conservative website similar to the teaching that I grew up with.  So, I ask the question again.  Can these three parts be separated?   Can one exist without the other? What do you think?