▼tn Heb “arose,” the verb קוּם (qum) in this context certainly must describe a less ceremonial act. The entire country woke up in terror because of the deaths.

▼tn The noun is an adverbial accusative of time—“in the night” or “at night.”

▼sn Or so it seemed. One need not push this description to complete literalness. The reference would be limited to houses that actually had firstborn people or animals. In a society in which households might include more than one generation of humans and animals, however, the presence of a firstborn human or animal would be the rule rather than the exception.