Why does it say "Yomam Yefageshu Choshech"?
Rashi: Their counsel is not done. The light of their Chochmah is reversed to darkness.
Devar Eliyahu: There are two kinds of punishments. Some have a desire, e.g. for grandeur or honor, and do not attain it - "Yikav l'Or va'Ayin." Also refer to 5:14:2:1.
Malbim: This refers to annulling Resha'im's counsel. He darkens for them - the light of their counsel does not exist at all.
Why does it add "vecha'Laylah Yemashesheu va'Tzaharayim"?
Devar Eliyahu: A second punishment is one who attains wealth and honor, and suddenly his downfall comes and he is broken.
Malbim: This refers to the crafty being caught in their schemes. The light of their counsel exists, but they grope as if it is night, for their counsel is reversed to evil for them.
