ועתה ישראל מה ה' אלקיך שאל מעמך כי אם ליראה את ה' אלקיך ... (י-יב)
The Chovos HaLevavos explains that Hashem created you for one reason - to give to YOU. Hashem is magnanimous, loving and kind. Hashem wants to share of His good. Hashem made you - not because you were worthy, not because of anything that you did, nor because of anything that you will do. Hashem made you for one reason: to give to YOU.
But what does Hashem want from YOU? What does He really desire from YOU? He gave you 613 laws, plenty of holidays and thousands of customs, but what is the purpose of it all? What is the raison d’être of a Jew?
The answer is three words: "כי אם ליראה" - TO FEAR HIM, and serve Him with all your heart and soul.
In essence, all of our material accomplishments are meaningless, and in the world of truth we will not even be given credit for how much money we’ve made, because in truth, these are not OUR accomplishments. Hashem makes them happen through us. As R’ Emannuel Tehilla shlita verbalized so profoundly, “What we HAVE is Hashem’s gift to us; what we BECOME is our gift to Hashem!” The only REAL accomplishment in life, and truthfully the entire purpose of our lives is Fear of Heaven, as Chazal teach: “Everything is in the hands of Heaven except for Fear of Heaven.”
Moshe Rabbeinu told the Jewish people to fear Hashem, making it sound like a simple matter because he himself had reached such a high level in this area that it was natural for him (ברכות לג). However, for the rest of us, it is no simple matter. Fear is the natural instinct of a person when there is danger involved. But fearing Hashem is foreign to the human psyche and requires continuous reminders and exercises to work on. The 613 mitzvos and thousands of minhagim, are all aids so that we may apply our intellect to understand what we are doing in order to be imbued with Yiras Hashem through performing His will. This is the goal of all the mitzvos, and if we succeed in this area we have achieved the purpose of life!