יָחֻ֙לוּ֙ עַל־רֹ֣אשׁ יוֹאָ֔ב וְאֶ֖ל כָּל־בֵּ֣ית אָבִ֑יו וְֽאַל־יִכָּרֵ֣ת מִבֵּ֣ית יוֹאָ֡ב זָ֠ב וּמְצֹרָ֞ע וּמַחֲזִ֥יק בַּפֶּ֛לֶךְ וְנֹפֵ֥ל בַּחֶ֖רֶב וַחֲסַר־לָֽחֶם׃
let it fall upon the head of Joab, and upon all his father’s house; and let there not fail from the house of Joab one that hath an issue, or that is a leper, or that leaneth on a staff, or that falleth by the sword, or that lacketh bread.’
Rashi on II Samuel
[The guilt] should fall. The [guilt of the] blood of Avner should rest, should fall. [This verse is] referring back to the preceding verse that stated, I and my kingdom are innocent from [the guilt of] the blood of Avner [The guilt of] his blood should fall on the head of Yoav. The blood [of Avner] that was mentioned in the previous verse.
Rashi on II Samuel
[A lame person] who leans on a cane. Who leans on his cane because of diseased feet.