We may infer from the text of the pasuk that the curses to which Klal Yisrael will be subjected are a result of serving Hashem without joy. In other words, regardless of one’s actual performance of a mitzvah, if it is not carried out joyfully it is not considered to be a mitzvah. To the contrary, it is a source of curse. The commentators explore the importance of inherent joy in mitzvah performance. The Baal Ha’Tanya offers a profound explanation for this. Unhappiness indicates a total breakdown of personality. A true Jew must be happy! He is blessed — either physically or spiritually — and should have faith in the Almighty, the Source of all blessing. Such a person, who is content with his lot in life, radiates the joy that permeates his essence. Something is wrong with the spiritual constitution of a Jew who does not serve Hashem with joy and excitement. Happiness is a critical component of the Jewish psyche.
Let us expand on this idea. Joy is central to living a Torah life. In fact, it is the essence of spirituality. Spiritual joy is dependent upon one’s feelings of self-worth and contentment that his life has a purpose which gives significance to his existence. One who has low self-esteem perceives no purpose in life and there is no significance to his existence. This is kefirah, apostasy! To denigrate oneself is to allow oneself to become vulnerable to idol worship. Indeed, missionaries for every worthless creed are able to prey upon people with low self-esteem.
Mitzvos, G-d given commandments, reflect the premise that Hashem wants us to conduct ourselves in a specific manner. What greater source of joy can there be than the awareness that the Supreme Ruler of the world seeks a relationship with us ? What greater purpose can there be in life than the realization that every action we make, every endeavor we undertake, has the goal of generating nachas ruach, satisfaction and pleasure, for Hashem ?
As we become increasingly aware of our relationship to Hashem, we should be imbued with an increased feeling of self-worth and a heightened sense of joy. This feeling should inspire everything we do and refresh our spirits with the knowledge that we are engaged in fulfilling Hashem’s mandate.