Bereshis 25:21-23 Orthodox Jewish Bible (OJB)
21 And Yitzchak davened to Hashem on behalf of his isha, because she was barren; and Hashem was entreated of him, and Rivkah his isha conceived.
22 And the banim struggled jostling within her; and she said, If it be well, why am I thus? And she went to inquire of Hashem.
23 And Hashem said unto her, Two goyim (nations) are in thy womb, and two peoples shall be separated from within thee; and the one people shall be stronger than the other people; and the older shall serve the younger.