The title of one of Lévinas’s essays included in Difficult Liberty contains a mild expletive, “nom d'un chien,” which is difficult to translate into English. It is a stand-in for a stronger French expression of surprise which takes the name of God in vain. Some people use the term “bitch” in English with about the same set of nuances. The idea is that life confronts us with things that surprise us and we don’t whether to associate God with them or a despised animal.
In a splendid little essay first published in a Festschrift for Bram Van Velde in 1975, Lévinas thinks about dogs. He relates the dog of Exod 11:7 to a stray dog he and fellow Jewish POWs confined to camp 1492 in Nazi Germany came to know during enforced labor outside the camp.
Everyone around them saw in them, because they were Jews, beings less than human. They were not welcome because they were Jews. For the Nazis, they needed to be wiped off the face of the earth.
The dog was different. “For him,” says Lévinas, “there was no doubt we were human.” For the Jewish POWs, the stray was, as the saying goes, “man’s best friend.”
The Egyptian dog of Exod 11:7, Lévinas points out, is similar. The dog does not sharpen his tongue against the Israelites, though they were nothing but slaves, the night they escape from the land of their overlords.
Levinas read his experience in the light of the Bible and the Bible in light of his experience. The stray dog knew who he was even if the whole world no longer knew. A demonstration, as it were, of natural law.
The dog of Exod 22:30 is also explained by Lévinas. There the command is given to throw to the dogs meat which cannot be consumed by human beings:
Beyond all scruples, by virtue of its happy nature and direct thoughts, the dog transforms all this flesh cast to it in the field into good flesh.
A Christian who reads this will remember the events of Acts 10. For Peter, the thought of having to receive Gentiles into the Jewish faith as he understood it created a sense of revulsion and impurity within him. It was as if God was asking him to become the dog of Exod 22:31.
Perhaps God was.
 Emmanuel Lévinas, Difficult Freedom: Essay on Judaism (tr. Seán Hand; Johns Hopkins Jewish Studies; Baltimore: Johns Hopkins University Press, 1990 [1963, 1976]). The essay in question is “Nom d'un chien ou le droit naturel,” 151-53.
 “A dog will not whet his tongue against any Israelite, against man or beast, that you may know that the Lord makes a distinction between Egypt and Israel.”
 “You shall be a holy people to me; you must not eat kill found in the open; you shall cast it to the dogs.”