"Speak to the Children of Israel and say to them: A man or woman who shall dissociate himself by taking a Nazirite vow of abstinence for the sake of Hashem.
From new or old wine shall he abstain and he shall not drink vinegar of wine or vinegar of aged wine: anything in which grapes have been steeped shall he not drink and fresh dried grapes shall he not eat."
"All the days of his Nazirite vow a razor shall not pass over his head until the completion of the days that he will be a a Nazirite for the sake of Hashem, holy shall he be, the growth of hair on his head shall grow." The Ba'al HaTurim connects consecutive sections of Parshat Naso with Adam and Chava.
The section of Sotah (suspected Adulteress) according to the Ba'al HaTurim is connected to Adam and Chava. One of the punishments for adultery and a result of drinking the bitter waters prescribed was that the legs fall off the adulteress. The snake who caused Adam and Chava's sin, as a punishment, lost his own legs which formerly had allowed him to walk vertically. The section of Nazir follows the section of Sotah because the fruit that Adam and Chava ate were grapes according to the Ba'al HaTurim (there are differences of opinion on what the fruit was). The Nazir is a Tikkun (rectification) for Adam's sin.
The Grape represents wine which caused Adam's downfall as well as so many through the millennia. Spiritual damage is caused by misusing the physical world. It started with Adam.The grape plays a major role in Kiddush, Brit Milah, the Marriage Ceremony and other Holy Events-as part of a rectification process and as a way of channeling the spiritual energy of wine. Wine represents Da'at, specifically Da'at Torah. This is alluded to by the fact that the word "Sod" (gematria 60+6+4=70) which is the ultimate Da'at of Kabbalah is equal to the gematria of "Yayin" (10+10+50=70). The Nazir rectifies the sin of Adam further. By abstaining from wine the Nazir re-creates the Pre-sin state-the pristine state of Gan Eden.The Nazir prevents sin by abstaining from wine.
The grape in essence caused man's downfall. This explains why the Nazir abstains from wine. Why must he not cut his hair? It would be easy to say that Adam and Chava would not have cut their hair in Gan Eden which is Man in his most Natural State. But it is much deeper. The Haftorah for Parshat Naso is about Shimshon HaGibbor. Shimshon was a Nazir. Shimshon was forbidden to cut his hair at all, while a regular Nazir would make his vow only for a specified period usually 30 days. Now follows a Kabbalistic understanding of the hair of a Nazir.
The Zohar on Parshat Naso explains that the Nazir alludes to the divine Partzuf of Arich Anpin, the "long face", which stands as Keter, the crown over Zeir Anpin which is the "small face" whereby G-d is revealed to the world. The sweetness of Arich Anpin rectifies the harsh punishment of Zeir. Thus the attributes of the Partzuf of Arich Anpin includes long white hair, which is bound up with the concept of the long hair of the Nazir (each strand of hair-Se'ar-is a Sha'ar or Gateway-a channel for divine light). The strands of hair are actual passageways of G-d's light to Man (exemplified by Shimshon) particularly into his Brain.
The hair are revelations of G-d's Kindness therefore must not be cut. Shimshon when his hair was cut lost the Schechina. They were if you will "electrodes" by which G-d communicates his Schechina. This was all part of Pre-sin Man in Gan Eden. The Ari in Likutey Torah on Judges says that Shimshon was the Gilgul of Adam Ha Rishon. Shimshon had the power to rectify Adam's Sin but fell into the Kelipot just as Adam did. The Nazir is an attempt to reach the highest spiritual level possible in the physical world. It is an attempt to Get Back to where we used to be. Man was placed into Gan Eden at the highest level possible. It is up to each and everyone of us to emulate the Nazir and try to reach that level as best as we can each according to their abilities. Shabbat Shalom