Proverb 3:1

“My son, do not forget my law,
But let your heart keep my commands;”

Do not forget.

Write it down, talk about it, study it, memorize it. Do whatever it takes so that you don’t forget the law.

“But”, (suggesting the alternative here) let your heart keep my commands. As in you determine, by allowance, whether or not your heart will keep the commands–by whether or not you are remembering them. If you forget, the commands will not be kept. 

Do your due diligence, daily to remember the living law.

And remember to live the law.