In the Law of God all of man's responsibility is carefully laid out - Jesus summed up the Law in Mark 12:29-31 (also in Matthew 22:37-40)
The beginning of the commandment states that 'Our Lord is one Lord'. The Hebrew word for one means united, ie. one or first - it comes from the root word that means to unify. The Hebrew word for Lord means the self-existent or eternal - it comes from the root word that means to exist, ie. be or become (I AM). Our God is triune - Father, Son, Holy Spirit. Yet they are one unified existence - whole, complete, and not able to be divorced from each other. What is the unifier that holds them fast to each other? The bond between Father, Son, and Holy Spirit is LOVE. It holds Them so tight to each other that nothing can separate Them. This same 'bond of perfectness' - love - is what God desires for man, ie. to hold man to God and man to man.
The bottom line - 'God is love' (I John 4:8b). God loves man without measure - with the same love that THEY love Themselves with. The reason - God spoke to God to make man (Gen. 1:26,27) - man comes from the essence of God. Father sent the Son to buy back Their own essence - man's trapped eternal spirit. Awesome! God's goal as stated in Col. 3:14,15 is that man would grow up in love - bonded together - whole in his love of himself, whole in his love of mankind, whole in his love for God (loving God with every part of his being). And ruled by the peace of God in his heart.
'Love God with all your heart' - perfection - realm of God the Father. The Greek word for heart (Kardia) means the middle, center of being. The Hebrew word means the heart as the most interior organ - from the root word that means to be enclosed. We are to love God with all the center of our being.
When we love God with all our center than our heart is perfect toward God. The word perfect (shalem) is related to the word for peace (shalom). Shalem means complete, friendly - a perfect heart is not only whole but 'user-friendly' to God.
Perfect (shalem - complete) peace (shalom). The word for mind in Hebrew means a form - from the word that means to mold into a form (like a potter). Staying this 'form' on God produces complete peace. Therefore the 'heart' and 'form' are the one and the same thing. Loving God with all the heart cancels out the temptation 'ye shall be as God' (Genesis 3:5) putting man back under the dominion of God the Father.
Satan's statements to Eve in Genesis 3:5 challenged the dominion of each member of the Trinity - the sin had to be against each one for it to be complete.
'Love God with all thy soul' - transformation - realm of God the Son - Jesus. The Greek word for soul is pusche. Both the Greek and the Hebrew words for soul mean breath, to be breathed upon.
When God breathed into man's body He fused the heart to the body producing a living soul (a living breath). Breathe is not solid, yet according to scripture it lives.
Note it was the voice that walked - a good definition for Rhema. Man is a living breath like Jesus is the voice that walked. The living breath is the seat of man's life -it is what he is to lay down.
Neither Deuteronomy nor Matthew tell us what a living breath is - but Mark does.
'Love God with all thy mind'. The Greek word for mind is nous - it means all understanding in thought (mind), feeling (emotions), and/or will - the conscious rational being - what we commonly call the soul.
The word understanding is dianoia - which means deep thought. It comes from the root word nous (mind, will, emotions). When we love God with all our breath and mind our eyes are enlightened - we will see God through the eyes of light not the darkness of the eyes of flesh.
Before the fall man's eyes were closed. A closed eye can see naturally the full spectrum of light - both spiritual and natural. It is more closed than the pupil of the eye is closed in bright light. A 'closed eye' is a 'single eye' - full of light. Single means folded together, like braids, plaits, twine - similar to the Hebrew word one - unified. The light of love makes the eye single by braiding man's being together so that it is unified. After the fall man's whole being was fractured like a prism. His eye was opened - like the natural eye is opened, dilated by darkness. An 'open eye' is an 'evil eye'. Evil means hurtful, derelict, diseased, culpable, ill. It can only see some of light's spectrum - only the natural world. It is an eye open to the darkness of the tree of the knowledge of good and evil but closed to the tree of life. It is under the law of sin and death - therefore it produces death. When we love God with all our breath and mind, it cancels out the temptation 'your eyes will be opened' (Genesis 3:5) restoring the dominion of God the Son, Jesus.
'Love God with all thy strength' - sanctification - the realm of the Holy Spirit. The Greek word for strength is ischus - it means force, ability, might. The Hebrew word is might - it means vehemence, ie. vehement, wholly, speedily.
Man is to yield his strength, his body and all its members, to the service of the Holy Spirit who works sanctification in man.
The Holy Spirit teaches man all things (especially about Jesus). When we love God with all our strength, the temptation to know good and evil a part from God is cancelled and the dominion of the Holy Spirit over man is restored.
When God has worked His love in us so that we love God wholly, then the first commandment is fulfilled. Father longs for us to love Him wholly. Love is not satisfied until it is reciprocated. Until we love God with all of our being Father's heart remains in a longing state - searching 'to and fro throughout the whole earth', looking for that one whose heart is perfect to Him'.
We are to love God with our body, soul, and spirit. We are to love ourselves wholly. We are to love man as we love ourselves - wholly. We are to love man with our strength, with our breath and mind, with our heart - Father's love extended to our world. Love so deep that it longs like Father longs for love to be known, revealed, shown.