We find various rabbis in rabbinic literature who built their spirituality through fasting and depriving themselves of physical pleasure. Rav Kook explains that this is like "shock treatment" or bitter medicine, which healthy people don't need. In Torat Eretz Yisrael, the Living Torah most applicable to the modern world, the approach of unity is to reveal the harmony between the physical and spiritual worlds. In Israel, where even the physical is spiritual and the atmosphere is Jewish, it's much more conducive to living a life of modern orthodoxy without the dangers of losing our proportions, priorities or getting influenced by western society. Accordingly Rav Kook explains the machloket between Rava & Abaye in Masechet Shabbat.
Rav Kook sees that the nature of Tshuva is among the most basic of ideas to understand life & the world. The sinner lives a life of self-centeredness, who inevitably will have difficulty finding love & lasting relationships, seeing the world as chaotic & pessimistic. Children eventually mature, learning to share & give. Kabbala refers to the pessimists who see our 3 dimensional world as Alma D'Piruda, "World of Division", rather than the believer in Unity & God, Who created a world of harmony. The Torah teaches how to find harmony in a complex world. One can see the violence in the animal world as chaotic, but if one steps back & views the entire picture he sees a harmonic orderly food-chain. All creation follows God's program, & man would be wise to choose so, as well, and "Join the Unity".
There's a common scenario, where someone becomes a Ba'al Teshuva, strengthening himself religiously, & indirectly, davka becomes less Zionist! Rav Kook ironically deals with this issue way before it was common, as part of his overall & innovative understanding of Teshuva, in this classic letter to his student, R. Charlap. Explaining that the concept of Evolution is the basis of Creation, & that constant improvement is the most natural process for the individual & mankind. This central drive is what's behind most of Torah, life and goals. Zionism is the easiest way to see God today, thru how He runs processes of advancement in history, fulfills prophecies, returns Altruism and Nationalism to their proper place, reviving the "Or LaGoyim" etc.
We all know that if you don't have a goal, you can't score! We all have many goals, but is there one which encompasses and is the common denominator of them all? Such a definition will prevent us from feeling torn between the many goals and roles we have. One theory is that the goal of life is pleasure, which is the common denominator of all people. On the other hand, all those people also have an ideal for which they are willing to forego all of their pleasure, inferring that ideals supersede pleasure! The class suggests that these 2 theories are 1 and the same, for we all want pleasure, but ideals are not 3rd class (short-term) pleasure, nor 2nd class (long-term) pleasure, but rather 1st class, eternal pleasure.
Innovatively but based upon the sources, Rav Kook entirely changes our view of T'shuva. The period of Elul until Yom Kippur is unfortunately, seen by most as depressing. Although we know T'shuva is important, we don't enjoy it & don't like changing. The mistake stems from the mistranslation: "Repentence" from "sin". Accordingly, Tshuva has terrible "PR", where the religious see it as something for the non-religious, and the non-religious say it's for the religious! Rav Kook says that the world is based on constant "Evolution" and improvement. Sports records are constantly improving, & toothpaste is always "new & improved!" Mankind and man improve thru "Trial & Error", & the most natural thing in the world is to follow the tide & improve!
There was another story of a non-Jew who came before Shammai and requested of him: “Convert me on condition that you will teach me the whole Torah while standing on one foot.” Shammai pushed him with the amat habinyan (building measuring stick) that was in his hand.