וְהֵשִׁ֣יב בְּךָ֗ אֵ֚ת כָּל־מַדְוֵ֣ה מִצְרַ֔יִם אֲשֶׁ֥ר יָגֹ֖רְתָּ מִפְּנֵיהֶ֑ם וְדָבְק֖וּ בָּֽךְ׃
여호와께서 네가 두려워하던 애굽의 모든 질병을 네게로 가져다가 네 몸에 들어붓게 하실 것이며
Rashi on Deuteronomy
אשר יגרת מפניהם [HE WILL BRING UPON THEE ALL THE DISEASES OF EGYPT] OF WHICH THOU ART AFRAID — i.e. afraid of the plagues (not of Egypt). When the Israelites saw the strange plagues that came upon the Egyptians they were afraid of them — that they might not befall them also. You may know this, for so it states, (Exodus 15:26) “If thou wilt indeed hearken [to the voice of the Lord …], none of the diseases which I have put upon Egypt, will I put on you”, since one threatens a person only with things of which he is afraid.
Siftei Chakhamim
The proof is that the following is written, “If you obey etc.” But one cannot prove anything from the verse here where it is written, “which you dreaded,” because you could say that “which you dreaded” refers to the Egyptians and means as follows: “All the Egyptian diseases,” and which Egyptians? Those “which you dreaded.” Therefore Rashi has to prove this from “If you obey, etc.”