Based on a shiur of Harav Itcha Meyer Morgenstern Shlita
One of the attributes that draws us to our Tzadikim is the tranquility that shines from their faces. We draw strength from the simcha and menuchas hanefesh that radiates from the unshakeable emunah of a Tzadik, who is never “thrown off” by anything. Rav Itcha Meyer said in a shiur that this is such a foundational middah of a Tzadik, that a sign by which you can determine whether someone is a true Tzadik is whether he has tranquility and joy shining from his face.
One of the talmidim at the shiur asked him if this also applies to chumros and dikduk halachah – meaning, should one try to always live with tranquility and joy, even while he passionately and meticulously strives for the highest level of stringencies in Halachah? Or perhaps it is okay to “stress” over such matters of ruchniyos, over whether he is going to be able to do the mitzvah in the absolute best and most ideal possible way.
Rav Itcha Meyer answered that it depends where these feelings bring the person. If he understands, while in a place of yishuv hadaas (calmness), that the Will of Hashem is that he be meticulous in fulfilling the mitzvah in the absolute best possible way, then then this drive is coming from the side of kedushah, and he should push himself with great strength to do so. But if the desire to do these chumros is being driven with anger, or sadness, or similar emotions, one must know that such pressure is always from the klipos.
The same rule applies to the way a person reflects back on how he did a mitzvah after the mitzvah is complete. If a person feels that he did not do that mitzvah properly, he should analyze where such feelings are bringing him. If a person feels regret that he did not do the mitzvah in the best way, and this brings him to teshuvah and a resolve to do it better the next time, that is an indicator that these feelings are being driven by the side of kedushah.
But if these thoughts bring him to sadness and despair, and he feels like he just experienced a terrible spiritual decline and it brings him to lose hope, that is a sure sign that such feelings are being driven by the klipos, who are always trying to drag a person down and bring him to despair, knowing that this will lead him away from avodas Hashem. If this happens, one should try to do anything he can to distance such feelings from his heart.
This article was found in Nekuda Tova Issue 36.