The heart is desperately wicked, who can know it?
The answer is in the next verse: God can know it.
This is kind of a problem for us. We live with ourselves so we are accustomed to our sins, so much so that we call most of our sins our “personality.”
People have a phenomenal ability to justify their sins and think they are good. But the wickedness of our heart defies knowing. It’s worse than you can imagine. Here’s one glimpse into it.
“Because they [the wicked] regard not the works of the LORD, nor the operation of his hands, he shall destroy them, and not build them up.”
Everything that happens in your life is a work of God, an operation of his hands. When we do not acknowledge this, say thank you, or even cast a glance His direction, we sin.
We are oblivious to God’s working. Instead we assume that we control all things. We sound too charismatic or superstitious or too something or other to see God at work in all things.
So we ignore Him, chalk up our victories to our own effort and our losses to our spouse’s efforts and carry on.
Sin.
This is a single facet of the incurable, desperate wickedness of our hearts.
anti-itch meditation 
Jeremiah 17:9
The heart is deceitful above all things
and beyond cure.
Who can understand it?
God has given us a tool which can expose all deception- His Word
Certainly the word sheds its light and reproves the hidden works of darkness, but I still think our level of evil is beyond our comprehension. That’s why I am continually amazed at how many more sins seem to be revealed to me in my own life! It never stops!
The greatest deception is the folks who think they are accepted by God, and believe they are pure and undefiled, even though they are only hearers of the word and not doers. I know I’m a sinner, but I’m trusting Jesus will enable me to do all he has called me to do. (Phil 4:13).
Love your blog brother.