In Steinbeck’s East of Eden, his sustained meditation on good and evil whispers to us the great and terrible blessing, “timshel.”
The Hebrew for “you may,” God says “timshel” to Cain after Cain’s offering is rejected. In Genesis 4, as Cain broods over his perceived injustice, God says, “If you do well, will you not be accepted? And if you do not do well, sin lies at the door. And its desire is for you, but you may (timshel) rule over it.” 
Theologians and Bible scholars have debated the exact meaning of timshel. Is it a prediction, meaning that “you will” rule over sin? Is it a commandment, meaning “you should” rule over sin?
Steinbeck’s stand-in, Lee, undergoes a obsessive journey to arrive at the interpretation, “you may,” referring to our choice. Good or evil, heaven or hell, in our hands. 
At lunch with friends, after joking and catching up, we got to talking about regrets. How we’ve hurt people that we care about and how we hurt ourselves in the process. How I once cut a friend out of her share of a business arrangement because I found her personality challenging. Or how my pal, CH, publicly humiliated his gay friend in a misguided display of evangelizing.
Some of these things can be fixed. And most can’t. Either way, we tarry forward.
This is how God blesses us, as he blessed Cain. That whatever has been done to us or by us, by our hands or by his. Still, timshel.
 New King James Version, italicized “may” mine.
 For a wonderful look at East of Eden as midrash, which inspired and informed my post, see Timshell Farms’ “Timshel Thou Mayest.”