"and you shall not go out, a man from the door of his house: We are hereby taught that once permission has been given to "the destroyer" to destroy, he does not distinguish between the righteous and the wicked. As it is written (Isaiah 26:20) "Go, My people, enter your chambers and close your door behind you. Hide but a little moment, until the wrath passes," and (Ezekiel 21:8) "Behold, I am (coming) upon you, and I will draw My sword from its sheath, and I will cut of from you (both) righteous and wicked."
And it is written (Exodus 33:22) "And it shall be, when My glory passes by … and I shall cover you with My palm until I have passed." Variantly: (Exodus 12:22) "And you, do not go out, a man from the door of his house until morning" — to teach you that when you take to the road, enter (the house) in "ki tov" (i.e., in the morning) and leave in "ki tov" (from Genesis 1:4 "And G–d saw the light ki tov" ("that it was good").