http://revach.net/article.php?id=2988

Section: Taryag Mitzvos   Category: Mitzva Opportunity
What Is Your Mitzva?
The Sefer Chareidim says that even though a person must keep all the mitzvos, still each person should have one mitzva that he holds onto with all his might.  You must know all the halachos inside out and be careful to keep this particular one to the "nth" degree.  He explains that the the Torah is a tree of life.  In order to attached yourself to it you cannot grab hold of the whole tree in its entirety, rather you grab hold of a single branch and through that branch you lift yourself onto the tree. 

We see this in the gemara where an Rav Yosef the son of Rabbi is asked about his father, which mitzva was his "specialty".  We see many gedolim were famous for their caution in a certain mitzva.  Rav Naftali of Ropshitz once said that his neshama is tied to the mitzva of Succah and every single day of the year he is somehow involved in that mitzva.

This would explain the enigmatic memra of Rebbi Chanaya ben Akshaya who says that Hashem gave us many mitzvos as a great favor.  You would think that less mitzvos would be a greater favor, so as not to leave us so much room for error.  In light of the Chareidim, we see that it is a great favor to give us tree with so many branches to climb on to.  If one branch proves too difficult an access point for us, we have many other choices.

So go ahead choose a mitzva, any mitzva.  The choices are endless.  Climb up and hold on to the tree of life!