כִּֽי־אַתֶּ֣ם יְדַעְתֶּ֔ם אֵ֥ת אֲשֶׁר־יָשַׁ֖בְנוּ בְּאֶ֣רֶץ מִצְרָ֑יִם וְאֵ֧ת אֲשֶׁר־עָבַ֛רְנוּ בְּקֶ֥רֶב הַגּוֹיִ֖ם אֲשֶׁ֥ר עֲבַרְתֶּֽם׃
你們知道我們從前怎樣住在埃及地，也知道我們怎樣從你們所經過的列國中間經過；
Rashi
כי אתם ידעתם וגו׳ FOR YE KNOW [HOW WE HAVE ABODE IN THE LAND OF EGYPT] etc. — The meaning of these verses is: Because you have seen the conduct of the other nations, and perhaps the heart of one of you might beguile him to follow them, — as it goes on to state, “Lest there should be among you a man, or a woman … [whose heart turneth away this day from the Lord]”, — on this account I must place you under an oath.
Ibn Ezra
you have known… There are some among you who have witnessed the abominations of Egypt (i.e., their gods), and all of you have witnessed the abominations of the other nations.
Ramban
FOR YE KNOW HOW WE DWELT IN THE LAND OF EGYPT etc. AND YE HAVE SEEN THEIR ABOMINATIONS. Because you have seen the nations that worship idols, and perhaps the heart of one of you might beguile him to follow them.