2,882. Conflicting Nazirite Vows

Hilchos Nezirus 4:8

If someone says that he will be a nazir after 20 days have gone by, then he says that he’s permanent nazir effective immediately, the first vow never takes effect.

Hilchos Nezirus 4:9

Similarly, if someone says that he will be a nazir like Samson after 20 days, and then he says that he’s a nazir effective immediately, he doesn’t shave for the second vow that he made.