Matthew 22:36-40 NKJV

  Matthew 22:36-40

(36) "Teacher, which is the great commandment in the law?" (37) Jesus said to him, "'You shall love the LORD your God with all your heart, with all your soul, and with all your mind.' (38) This is the first and great commandment. (39) And the second is like it: 'You shall love your neighbor as yourself.' (40) On these two commandments hang all the Law and the Prophets." 

  Mark 12:28-31

(28) Then one of the scribes came, and having heard them reasoning together, perceiving that He had answered them well, asked Him, "Which is the first commandment of all?" (29) Jesus answered him, "The first of all the commandments is: "Hear, O Israel, the LORD our God, the LORD is one. (30) And you shall love the LORD your God with all your heart, with all your soul, with all your mind, and with all your strength." This is the first commandment. (31) And the second, like it, is this: "You shall love your neighbor as yourself." There is no other commandment greater than these." 

  Luke 10:25-28

(25) And behold, a certain lawyer stood up and tested Him, saying, "Teacher, what shall I do to inherit eternal life?" (26) He said to him, "What is written in the law? What is your reading of it?" (27) So he answered and said, "'You shall love the LORD your God with all your heart, with all your soul, with all your strength, and with all your mind,' and 'your neighbor as yourself.'" (28) And He said to him, "You have answered rightly; do this and you will live." 
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Jesus Christ's response to the Pharisee's question shows that He divided the Ten Commandments into two sections or tables. He covers the first four by saying, "'You shall love the LORD your God with all your heart, with all your soul, and with all your mind.' This is the first and great commandment" (verses 37-38). This supersedes all other commandments; none is greater. The second, covering the last six, is similar to it. "You shall love your neighbor as yourself" (verse 39).

God also arranged each section to begin with the most important command. He placed first the commandment, which, if kept, will ensure the greatest benefit to our lives, both physically and spiritually. On the other hand, if we break this commandment, it will cause the most damage to our worship of God or to the community by virtually ensuring that we will break others. In the first table of the law, this commandment is, "You shall have no other gods before Me" (Exodus 20:2). In the second, it is the fifth commandment: "Honor your father and your mother that your days may be long upon the land which the LORD your God is giving you" (verse 12).

Just as the first commandment governs our relationship with God, the fifth commandment is first among those that govern our relationships with men. When we keep it or break it, it affects those relationships. Not only is it chief in this section, it also acts as a bridge between the two tables of the law. When we keep the fifth commandment properly, it leads us to revere and obey God Himself.

— John W. Ritenbaugh