Is family planning permissible? And who are the Rabbinic scholars? Thank you.

The exegetes (scholars of Qur'anic exegesis) differed regarding the origin of the word "Rabbaniyyin." Some said it is derived from "Rabb" (Lord), while others held that it is a Hebrew or Syriac word meaning "scholar." Still another opinion suggests it is derived from "Rabb" in the sense of upbringing or nurturing. Despite this اختلاف (disagreement), the comprehensive meaning of "Rabbani" is the scholar who acts upon his knowledge, teaches, adheres firmly to the religion of Allah and His obedience, and possesses insight into governing people.