משנה תורה, הלכות נזירות א׳:ד׳
When a person says: "I will not depart from the world until I become a nazirite," he becomes a nazirite immediately, lest he die at that time. If he delays [implementing] his nazirite vow, he transgresses the prohibition: "Do not delay in paying it." Lashes are not given for the violation of this prohibition.
לחם משנה על משנה תורה, הלכות נזירות א׳:ד׳:א׳
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