These two lines are parallel, with "Israel" and "the house of Jacob" meaning the same thing and "Egypt" and "that foreign people" referring to the same people. (See: [[rc://en/ta/man/jit/figs-parallelism]])
The word "house" here represents the family or descendents. The verb may be supplied to this phrase. Alternate translation: "the descendants of Jacob left people who spoke a language that the descendants of Jacob did not understand" (See: [[rc://en/ta/man/jit/figs-metonymy]] and [[rc://en/ta/man/jit/figs-ellipsis]])