The Gemora (Bava Kama 30 a) quotes Rav Yehuda that one who wishes to be a chasid (righteous and therefore spiritual person) should fulfill the precepts of damages, Rava says precepts of morals and others say precepts of blessings.
The Maharsha (Harav Shmuel Eliezer HaLevi Idlash ztl- remember the righteous for blessing) explains that each of these Amorayim (sages of Gemora) recognize the importance of each of the three precepts as contributing to the total of a persons’ spiritual existence.
There are 3 types of good deeds; good for others, good for oneself and good for Heaven. Working on each of the three precepts stated, perfects each of these areas. So perfecting one’s behavior regarding damages is good vis-a-vis others, morals is good vis-a-vis oneself and blessings is good vis-a-vis Heaven.
Therefore, Judaism is imbued with occurrences of three and almost all of them relate back to these three components of life. For example, 3 forefathers, 3 festivals and 3 daily services.
Spirituality in Judaism is intrinsically bound with physicality. More than this, physical existence is an integral part of spirituality in the Torah.
The Mishna is Pirkei Avos quotes Shimon Hatzaddik that on three things the world stands; on the Torah, on service (of Hashem – God) and on doing kindness. These are the three category headings for our three facets of life mentioned above.
Torah relates to one’s relationship with self, in as much as the Torah is the means by which one perfects one’s spiritual self. It is, in fact, the ultimate intrapersonal mitzvah. Avoida or service (of Hashem) encompasses all ritual endeavors that a person undertakes and doing kindness covers all interaction with others.
Therefore, Jewish spiritual education addresses all three components that constitute spiritual life in this world and the lack of any one constitutes a lack in the persons' completion as a Torah Jew.
The following articles explain how this works and how best to build spirituality through the Torah: