Parashas Naso · Passuk 6:02
Speak to the Israelites and say to them: If any man or woman explicitlyaexplicitly See note at Lev. 22.21. utters a nazirite’s vow, to set themselves apart for GOD,
Chabad.org — English translation + Rashi
Source: Nazir 2a.
English: “Speak\ldots” — it was taught: Rebbi says: Why was the section of the nazir placed next to the section of the sotah? To tell you that whoever sees a sotah in her disgrace should separate himself from wine.
In context: The juxtaposition is pedagogical: the spectacle of the sotah’s downfall should motivate abstinence from the intoxicant that leads to such ruin.
Custom
Chazal teach that witnessing the sotah’s ordeal should lead a person to take a nazirite vow against wine.