כִּי אִם אֵינְךָ מְשַׁלֵּחַ אֶת עַמִּי הִנԀנִי מַשְׁלִיחַ בְּךָ בַּעֲבָדֶיךָ בְּעַמְּךָ בְּבָתֶּיךָ אֶת הֶעָרֹב וגו' (ח, יז)
For if you do not let My people go, I will send upon you and your servants and your nation and in your houses a mixture of wild animals. (8:17)
The Dubno Magid zy’a notes that, in the Torah, the plague of kinim came before the plague of arov. However, the pasuk in Tehillim (105:31) says arov before kinim, which makes it sound like arov was first.
He answers this contradiction with a parable of a rich man who married off his son. In honor of the wedding, he made a lavish feast that lasted for seven days. On the first day, he invited all of his relatives. On the second day, he invited the Torah scholars of the town. On the third day, he invited all of the wealthy residents. On the fourth day, he invited all the poor people.
On the fourth day, he noticed that one of those in attendance had already been there on the first day. When he asked him why he had come back if he had already had a turn, the man said, ‐I am both a relative of yours and a poor man. On the first day, I came as a relative. Today, I came as a pauper.‐
Similarly, the kinim first came for makkas kinim. They returned for makkas arov, when all of the wild animals came. This time, they came in their capacity as a wild animal.