Bamidbar 6:3-4

Orthodox Jewish Bible

³ He shall separate himself from yayin and shekhar (fermented drink), and shall drink no chometz (vinegar) of yayin, or chometz of shekhar, neither shall he drink any grape juice, nor eat moist grapes, or dried (i.e., raisins).

⁴ Kol hayamim of his nazir (vow as a nazir) shall he eat nothing that is made of the gefen hayayin, from the seeds even to the grape-skins.