“I told you to empty yourself of emotion! … Fools who wear their hearts proudly on their sleeves, who cannot control their emotions, who wallow in sad memories and allow themselves to be provoked this easily — weak people, in other words — they stand no chance against his powers! He will penetrate your mind with absurd ease, Potter!”
Severus Snape.
The word “occlumency” found in the Harry Potter series comes from the word occlude, “to conceal”, and mens, Latin for “mind”.
The idle mind is the devils playground, sure. But is the most cluttered mind just as safe from his lies?
The art of concealing one’s mind never intrigued me until December 2011, when I realized my ignorance in protecting my own heart against distress bore down to a dreadful end of my year.
Fair enough, I was forewarned by the wise to close my mind. But I didn’t take heed. Never even tried. My night demons would come whispering release from suffering and I would succumb, barely fighting back.
For years it seemed I could get away with allowing him free reign over my thoughts, assuming because it wasn’t physical it couldn’t harm me.
And it didn’t. Not physically.
But emotionally I was preparing myself for my own downfall. Which came. Right before Christmas no less.
Above all else, guard your heart,
for everything you do flows from it.Proverbs 4:23

It’s ludicrous, what needs to happen before realization hits that protecting ones mind from him is priority, not placebo.
The heart is deceitful above all things
and beyond cure.
Who can understand it?Jeremiah 17:9
On a side note:

Thinking of: Bleeding for a good cause, occlumency, all good things that come to those who wait, God’s impeccable timing and going to sleep early!!!!