Here "Jacob" refers to the descendants of Jacob. AT: "Yahweh will have mercy on the descendants of Jacob" (See: [[rc://en/ta/man/translate/figs-metonymy]])
# attach themselves to the house of Jacob
The house of Jacob refers to the descendants of Jacob, the Israelites. AT: "unite with the descendants of Jacob" (See: [[rc://en/ta/man/translate/figs-metonymy]])
# The nations will bring them to their own place
"The nations will bring the descendants of Jacob back to the land of Israel"
# the house of Israel
This refers to the Israelites, the descendants of Israel. AT: "the descendants of Israel" (See: [[rc://en/ta/man/translate/figs-metonymy]])
# They will take captive those who had captured them