These are the people of Jerusalem that are still alive after Yahweh has finished punishing the city. This can be made explicit. Alternate translation: "some of the Israelites who escape the punishment of Yahweh" (See: [[rc://en/ta/man/translate/figs-explicit]])
# house of Jacob will be a fire ... Joseph a flame
Yahweh speaks of the houses of Jacob and Joseph as if they were fire because they will destroy Esau like a fire that quickly and completely burns up straw. (See: [[rc://en/ta/man/translate/figs-metaphor]])
The word "house" is a metonym for the family that lives in the house. In this case it refers to Jacob's descendants. Alternate translation: "descendants of Jacob" (See: [[rc://en/ta/man/translate/figs-metonymy]])