A Plague of Sound

 Why didn't the dogs bark on the night of the Exodus?

I never thought about it much until recently. I'd usually assumed that what the Torah really means by saying that the dogs didn't bark was that the Egyptians didn't protest when the Jews sacrificed lambs. Earlier, Moses had predicted that if the Jews were to sacrifice lambs in Egypt, then the Egyptians would stone them, because the lamb was considered a god (Shmos 8:26). So I'd thought that the Torah was using a kind of hyperbole: when the Jews actually did sacrifice lambs, not only did they not get stoned, the Egyptians didn't even raise their voices in protest, and even the dogs didn't bark.

It also reminded me of the trope that often appears in ghost stories, that humans can't see ghosts, but dogs can (and the dogs usually bark at the ghosts). During the plague of the firstborn, the angel of death came to Egypt, so you might have thought that the dogs would have barked at him, but they didn't.

When you read the pasuk in context, however, a different explanation suggests itself. (It's Shmos 11:6-7.) The previous pasuk talks about the screaming and wailing that will take place in Egypt when the firstborn die. The lack of dogs barking seems to describe the silence (peace and quiet) that will prevail among the Jews. As if the plague of the firstborn is not only a plague of death, but also a plague of sound.

This makes an interesting juxtaposition to the previous plague, which was a plague of darkness, so in a sense, a plague of light, or lack thereof: "For all of the children of Israel, their was light in their dwelling places." (Shmos 10:23)

The Artscroll commentary on the Chumash says basically the same thing: "In sharp contrast to the grief and death that will engulf the Egyptians, the Jews will enjoy complete tranquility; not even a dog will bark or how against them."