Sifrei Bamidbar Paragraph 33
Can copy this into an AI, or connect the whole library to your assistant. For deeper learning, you can directly use the original seforim, sites, and apps.
והקריב את קרבנו לה' כבש בן שנתו תמים להוציא בעל מום. וכבשה אחת בת שנתה תמימה להוציא בעלת מום ואיל אחד תמים [להוציא בעל מום] לימד לנזיר שטעון שלש בהמות.
Sifrei by Rabbi Shraga Silverstein
(Bamidbar 6:14) "And he shall offer up his sacrifice to the L-rd: one lamb of the first year, whole": to exclude one that is blemished. "and one ewe-lamb of the first year, whole": to exclude one that is blemished. "and one ram, whole": to exclude one that is blemished. We are hereby taught that the Nazirite requires three (mutually exclusive) animals (i.e., each is a mitzvah in itself).