@EzratHashem: Here’s my own synopsis of all the books I’ve read on this subject, shared successfully with teens who were looking for answers, not excuses.
All we have to determine is whether the Torah is true. If the Torah is true, Hashem exists and the Mitzvos are binding. Now, why would an entire people, a smart and stiffnecked one at that, accept a Torah that tells them BOTH:(a) You KNOW/SAW/HEARD ????? ?????, ????? ?? ???, ??? ???? etc., AND (b) Thou shalt… Thou salt not… 613 times, countless difficult commandments — unless they knew it was all true?
There are many other proofs, but this IMO is the most simple and irrefutable one.
Now for ???? ???? ?? – one proof and one example out of many:
Proof: the Torah doesn’t tell us how to shecht, only that we are to kill kosher animals “in the prescribed manner”. There must have been oral instructions for that.
Example: What’s ??? ?? ???? A beautiful bunch of grapes? A perfectly bright-maroon pomegranate with an intact crown? Perhaps the fruit of a beautiful tree, say the date palm? Why do all Jews, including ??????, ????? and others who mocked Chazal, take an Esrog? There must have been an unbroken oral tradition specifying what the Torah meant by ??????, ?????, ????? etc.
I don’t have all the answers. I don’t know why life has to be so difficult or why we have to do certain things. But since I KNOW that the Torah is true, and the Torah says many times that the world is good and life is good, I believe that everything has a good reason.
Once we have this straight, we can explore the meaning, beauty and joy of Yiddishkeit. Even if you haven’t found meaning, beauty or joy yet, that doesn’t free you from the obligation to keep all the Mitzvos. Sure, you have the RIGHT to live as you please, just as you have the right to become a druggie or shikker. Since the Torah is true, we know that the consequences are so severe, and the rewards for keeping it so great, that we really have no choice but to make the right choice.