4291. In the internal historical sense 'he said to him, What is your name? And he said, Jacob' means that they were the descendants of Jacob - together with their essential nature. This becomes clear from the meaning of 'name' as the essential nature, dealt with in 144, 145, 1754, 1896, 2009, 2724, 3006, and from the meaning of 'Jacob' as Jacob's descendants, dealt with above in 4281.
Ruth 2:13
13
η δε ειπεν ευροιμι χαριν εν οφθαλμοις σου κυριε οτι παρεκαλεσας με και οτι ελαλησας επι καρδιαν της δουλης σου και ιδου εγω εσομαι ως μια των παιδισκων σου