Lest they should either inflame or dispose him to luxury, and consequently to the breaking of his vow; or cloud his reason, and thereby occasion some mistake or miscarriage in the rules to which he had bound himself. Compare Leviticus 10:9. Nor eat moist grapes, or dried; which was forbidden him for greater caution to keep him at the further distance from wine.
Related Commentaries of Numbers 6:3
Numbers 6:3
3 He shall separate himself from wine and strong drink, and shall drink no vinegar of wine, or vinegar of strong drink, neither shall he drink any liquor of grapes, nor eat moist grapes, or dried.