Rashi on Numbers 6:8/רש"י על במדבר ו׳:ח׳

1כל ימי נזרו קדש הוא ALL THE DAYS OF HIS NAZARITESHIP HE IS HOLY — This refers to the holiness of his body which consists in his abstaining from defiling himself by reason of a corpse (Sifrei Bamidbar 27).