We have discussed many times in Psychology of the Daf (see Nedarim 78), Chazal were ambivalent about pious declarations of abstention, such as the vows of the Nazirite, and as the Gemara on daf 4b explains in regard to Shimon Hatzaddik’s suspicion regarding the sincerity of Nazirite vows. Yet, with proper intention and maturity to handle this period of abnegation, it can be a catalyst for humility and change. Our Gemara on Amud Aleph tells us that the Biblical juxtaposition of the Sotah ritual and the Nazir’s ritual hints at this. Whoever sees the Sotah in her degraded state, will swear off wine by becoming a Nazir.

This person who observed the moral downfall of the Sotah did not engage in finger pointing or moralizing. His thought was, if this upstanding Jewish woman could be tempted to sin, what are temptations that I am vulnerable to? Where do I have poor boundaries? He then swears off wine and other pleasures, as well as certain vanities, for a period of time, in order to rehabilitate.

As the Rambam points out in his introduction to the Guide for the Perplexed, the Torah speaks with hints, and especially in regard to complex moral issues, it is important to properly extrapolate and adapt its teachings beyond the literal. One does not need to actually become a Nazir, nor even abstain from wine, in order to take this lesson to heart. All it takes it to ask yourself, what can I learn and what do I need to do in response to this event? 

The Baal Shem Tov (Bereishis 126) states:

שנינו (במס' נגעים פ"ב משנה ה') כל הנגעים אדם רואה חוץ מנגעי עצמו, ופירש הבעל שם טוב הקדוש, כל הנגעים שאדם רואה חוץ, זה נמשך מנגעי עצמו, כמאמר רבותינו ז"ל (קדושין ד"ע ע"א) כל הפוסל במומו פוסל:(דברי שלום פ' קרח דנ"ו ע"ב).

We learned "a person sees all defects, except (chutz) their own defects" (Mishna Nega'im 2:5) and the holy Ba'al Shem Tov reads it as "a person sees all defects of the outsiders (chutz)" - what they see is a continuation of his own defects, as our sages say "he disqualifies others with his own flaw."