In order to be pious one would first need to observe all the mitzvahs scrupulously rather than simply, and with an eye toward the many details. In fact, lots of us overlook the finer details and are willing to settle for the broad outlines. But not the pious, and regardless of the type of mitzvah they are fulfilling.
For as most know, there are mitzvahs that we do at G-d’s behest alone that have not any apparent worldly benefits (like donning Tephillin or Tzitzit, and the like), and there are others that have clear societal benefits (like giving charity, comforting mourners and the like). And one could fulfill either type either “stingily”, so to speak, or generously when it comes to the details.
To be truly pious, one would need to be sure that his Tephillin, for example, were not only the requisite size, color, and composite of parts, but that it had been written by the best of scribes, who’d been as punctilious as he could be with the script, who’d taken pains to concentrate on the text he was transcribing in a spirit of holiness, etc.
The rest of us would certainly make the effort to buy halachically sanctioned Tephillin and to fulfil the mitzvah, but we’d nonetheless do without all the “ruffles and flourishes”, and would be satisfied with that. But not so the pious person. He or she would want every detail to be as perfect as is humanly possible.
The same care would go into his or her way of fulfilling the interpersonal mitzvahs we cited. While we’d all want to concentrate on the great good and betterment we’d bring into the world when we fulfill them, the pious would be keenly aware of all the circumstances involved, and extraordinarily sensitive to the needs and feelings of the people concerned, as we’ll explain.