During the lecture tour that Jabotinsky undertook in the winter of 1923, he arrived in Riga, capital of Latvia, where he met an organization of high school students called "Organization of Active Zionist Youth named for Yosef Trumpeldor", headed by Aharon Propes. This group formed the kernel of Betar (Covenant of Yosef Trumpeldor) Youth Movement, in which Jabotinsky saw the crowning glory of his Zionist activity. He advocated for the formation of a new Jewish type, "genius and generous and cruel". Genius, that is, standing straight, a daring fighter, generous toward his fellow man, who relates like a king's son to another king's son and cruel only toward himself. A generation free from diaspora complexes, always prepared to stand in service to his people. Jabotinsky reached the conclusion that, if the Jewish people aspires toward its own country, on the land of Eretz Israel, it make sure that a new generation would arise, educated and prepared for struggles. He motivated the dispirited Jewish youth to understand that the nation's fate was in its own hands, thus returning to the youth their self-respect, their national pride and the courage to live and also, to die – for example, Shlomo Ben Yosef, who, before going to the gallows, carved on his prison cell wall, "To die or to conquer the mountain", taken from the Betar anthem. Jabotinsky encompassed the Betar Doctrine in the Seven Principles of the Oath:

Zion: Only Eretz Israel has the power to solve the problem of the Jewish people and to ease the suffering in the dispersion;

Had-Ness: The basic principle distinguishing Betar from other movements is "Had-Ness" (Monism or one flag). The one flag, the supreme directive and the singular motivation of the Movement, is the ideal of establishing a Jewish state. Jabotinsky believed that "two ideals are absurd, truly like two gods, like two altars and two Temples…if Zionism is the ideal, no other independent aspiration, worthy of equal rights, can dwell alongside it".

Hebrew Language: The Betar Movement sees in the Hebrew language the national language, sole and eternal, of the Jewish people. A Jew who does not know Hebrew – is not a complete Jew.

Hadar (spirit of Betar Movement): A term encompassing external beauty, pride, respect, loyalty and many other lofty values – Hadar is the embodiment of humanity. 'Betar Hadar' is the aspiration of each and every one, every step and every act that the Betar member performs, must first be examined from the standpoint of Hadar.

Giyus (mobilization): The Betar member is prepared for each and any service for the sake of the people. Jabotinsky drew this concept from the unique character of Yosef Trumpeldor.

Magen (Protection): One of Betar's ideological principles is military preparedness. Betar demands that all its members complete military seminars and know how to use weapons, in order to be ready at any time and to respond personally to a call for defense.

Tziyut (Obedience): Voluntarily discipline. In willingness to obey, there is a type of contribution of strength for the people's effort and preservation of national stability and unity.