At that time, this was an acceptable way for a barren woman to have children that would legally belong to her. The full meaning of this may be made explicit. (See: [[rc://en/ta/man/translate/figs-explicit]])
This is a polite way of talking about sexual relations. You may need to use different words in your language. Alternate translation: "Have sexual relations with her" (See: [[rc://en/ta/man/translate/figs-euphemism]])
This is a way of saying that the child that Bilhah gives birth to will belong to Rachel. Alternate translation: "for me" (See: [[rc://en/ta/man/translate/figs-idiom]])