If you had to pick just one rule to live by, one rule to teach your kids, which one would you choose?  Jesus picked this one:

And 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. This is the great and first commandment.  (Matthew 22:37-38)

God is not emotionally needy; He is not hurt or impoverished by our failure to love Him.  So what’s the deal?  Why is this the most important one?  Let’s start with this: If we could truly wrap our minds around the reality that we have personally been created by an infinitely superior Being, Who designed and created the universe, Who knows us, cares for us and loves us, if we could hold that truth present in our consciousness, our natural response would be wholehearted love for Him.  Anything less would be petulant rebellion.  

Presumably, as we obey the command to love God with our all, it has the effect of bringing us closer to the full realization of Who He is and how He loves us.  Aligned with that truth, we are more in tune with the rest of His design.

But how would such love be expressed?  A Hallmark moment wouldn’t suffice. As we are drawn into a closer relationship of love with God, it spills over and is naturally expressed in our love for others.  That is why Jesus added this:

And a second is like it: You shall love your neighbor as yourself. On these two commandments depend all the Law and the Prophets.”  (Matthew 22:39-40)

Simply put, if you could truly obey the first command, you would find yourself obeying the second, and would not need to worry about all the others.