What is "b'Machashachim"?
Ibn Ezra: It is darkness amidst darkness 1 .
Ri Kara: It is not like "Asim Machshach Lifneihem la'Or" (Yeshayah 42:16); refer to 3:6:2:2.
R. Avigdor: It is poverty 2 .
What is the comparison to "Mesei Olam"?
Nedarim 64b: A blind person is considered dead.
Ri Kara: From the darkness of the dead, the world darkens.
R. Avigdor: The poor are considered dead. It says about Dasan and Aviram "Mesu Kol ha'Anashim" (Shemos 4:19) because they lost their wealth 1 .
Palgei Mayim: I had a prophecy of absolute darkness, like a Mes that is forgotten from the heart. So I despair of a cure.
Nedarim 64b learns this from Dasan and Aviram, and learns from our verse that a blind person is considered dead! Perhaps there is a major omission in the text of R. Avigdor. It should say 'a blind person is considered dead. The Gemara expounds that also others are considered dead. The poor are considered dead. It says about Dasan and Aviram