1)
How does he sweeten evil with his mouth?
1.
Rashi: If he desires to do evil, but sees that he would not succeed now, he conceals it, until he will be able to succeed.
2.
Malbim: This describes his sudden death. A healthy person with fine digestion, even if he eats bad food and poison, his mouth sweetens it, and 'denies' that it is bad; it does not harm him. We see nowadays that suddenly, one gets ill and vomits his food as if it was venom. It kills him suddenly, like poison.
