Thank you.
The question is raised by Chazal of whether there is greater reward for one who does something that is commanded, or something meritorious without being commanded. The Bavli in Kiddushin 31a concludes that one who does something commanded is greater than someone who does something voluntary. Commentators point out what the author of this Dvar Torah points out, that the yetzer hara is very powerful and to do something commanded requires overcoming that “Need To Be Free”.
But wait — there is a Yerushalmi that disagrees. In Shevi’it chapter 6, the Yerushalmi discusses the question of whether the oleh Bavil were commanded to keep the Shemittah year. The actual question isn’t really resolved (and in fact it remains a machloket even to this day) but they do say that if they did so without being commanded that was more meritorious than had they been commanded and if they were commanded but observed with joy their merit was increased to what it would have been had they done so without being commanded!
I have a resolution. The mitzvah given as the example in the Bavli is a personal one — honoring father and mother. The mitzvah example in the Yerushalmi is a communal one. When a community takes on a custom voluntarily there can be great merit, as it unifies the community — even though it is not commanded. But any individual mitzvah requires us to conquer our yetzer hara. I write this in memory of my mother o”h whose 28th yahretzeit is today. May I always be able to overcome my yetzer hara to honor this great intelligent woman who gave me so much, and may I always embrace my community’s minhagam.