What does the change from "a man shall not..." to "you shall not..." for one verse in Vayikra 20 signify?
In Vayikra chapter 20 the torah gives a long list of forbidden relations. Almost all of them are of the form "if a man (lies with, takes)..." or, in one case, "if a woman..." (third person). In Vayikra 20:19 the voice changes to second-person imperative: "you shall not...". What does the change in voice signify? The full verse here is (from Sefaria):
וְעֶרְוַ֨ת אֲח֧וֹת אִמְּךָ֛ וַאֲח֥וֹת אָבִ֖יךָ לֹ֣א תְגַלֵּ֑ה כִּ֧י אֶת־שְׁאֵר֛וֹ הֶעֱרָ֖ה עֲוֺנָ֥ם יִשָּֽׂאוּ׃
You [males] shall not uncover the nakedness of your mother’s sister or of your father’s sister, for that is laying bare one’s own flesh; they shall bear their guilt.
This isn't the first use of "uncover nakedness", though the earlier use (in 20:11) is less direct ("if a man lies... he has uncovered..."). The exact verb in the earlier "if a man..." verses sometimes varies, so I suspect it's not something special about the verb here.
Many of these prohibitions are also given in chapter 18, where they're imperative. In chapter 20 they're mostly third person, except for this one imperative verse.
None of the commentaries we had at torah study where we looked at this address this question, and I don't see anything in English on Sefaria that addresses it. I'm not proficient enough to understand the Hebrew commentaries there.