Leviticus 14:43

הִקְצוֹת — The grammatical form expresses the idea of something “having been done” (passive) and so, also, is the word הִטּוֹחַ (both are Niphal construct infinitive), but in חִלֵּץ את האבנים the expression refers to the man who removes them (i. e. it is active, the subject having to be supplied. The translation is: “after he has removed the stones”, whilst the following words denote: after the house has been scraped at its edges and after it has been plastered), it (the word חִלֵּץ) being of the heavy conjugation (Piel), just as כִּפֵּר and דִּבֵּר‎. ‎ ישוב מגע ‎ואם‎ AND IF THE PLAGUE RETURN [AND BREAK OUT IN THE HOUSE] — One might think that this means: if it returns on the self-same day it shall be unclean as it stated in v. 44. It, however, says, (v. 39) ושב הכהן “when the priest returns [on the seventh day]”, and here, also, it says, ואם ישוב, “and if it (the plague) return”. What is the case of “return” mentioned there? It is at the end of a week! Similarly, too, “return” mentioned here means at the end of a week (Sifra, Metzora, Section 7 6).

וְאִם־יָשׁ֤וּב הַנֶּ֙גַע֙ וּפָרַ֣ח בַּבַּ֔יִת אַחַ֖ר חִלֵּ֣ץ אֶת־הָאֲבָנִ֑ים וְאַחֲרֵ֛י הִקְצ֥וֹת אֶת־הַבַּ֖יִת וְאַחֲרֵ֥י הִטּֽוֹחַ׃

And if the plague come back, and break out in the house, after he has taken away the stones, and after he has scraped the house, and after it is plastered;