We have already stated that while pious abstinence is a desirable character trait, excessive abstinence is undesirable. It is undesirable for a person to deny himself pleasures to the point where he becomes sick, depressed, and bitter. In this regard it is written, "Do not be overly righteous" (Ecclesiastes 7:16) They also teach, "One who engages in fasting is called 'a sinner'" (Taanit 11a). Proper abstinence does not cause sadness; rather, it brings joy and a sense of freedom, a sense of valor: "Who is the truly valorous individual? The one who conquers his base instincts" (Tamid 32a).
Pious abstinence consists of three main ingredients: abstinence in the realm of pleasures, abstinence in the realm of laws, and abstinence in the realm of conduct.
We have already explained that abstinence in the realm of pleasures means refraining from superfluous worldly matters except where necessary. This includes foods, clothing, outings, as well as cohabitation. All of these matters call for pious abstinence from overindulgence, guarding the boundary between that which is necessary and that which is not. Pleasures must be channeled into conduits which involve fulfilling a mitzvah (commandment), like Sabbath, Festivals, or mitzvah-related celebrations.
Abstinence in the realm of laws means fulfilling commandments in the most desirable manner possible, to be stringent to the extent of recognizing even a sole dissenting view in a controversy if there is justice to it, even if the law is not decided in accordance with it. This, of course, is on the condition that the more stringent view is not actually more lenient relative to one's situation. It means not takings the easier alternative in cases of doubt, though permitted to do so.
Our sages of blessed memory explained the statement of Ezekiel (4:14), "My soul was not polluted" in the following manner: I did not eat of an animal about which a sage had to make a decision, even if it was deemed kosher. Because a question arose regarding its status, I refrained from partaking of it. Neither did I eat the flesh of an animal that had to be slaughtered quickly because it was in danger of dying. Even though it was permitted by law for consumption, I preferred to be stringent and distance myself from a possible transgression.
And Mar Ukvah said (Chullin 105a): My father, if he would eat meat today, would not eat cheese until tomorrow at the same time. But I am to my father as vinegar derived from wine, for I separate between meat and milk by one intervening meal.
Though there is no law which says that a person must wait so long, Mar Ukvah's father was stringent with himself. From here we can learn that in order to be stringent, one must be on a fitting level. It is not enough to merely imitate those who behave stringently. Therefore Mar Ukvah did not behave as his father did in this respect, for he felt that he was not on his father's level.
If a person practices pious abstinence and upholds numerous stringencies without being on the proper level, he probably possesses arrogance more than he does true piety. One must ascend to the level of pious abstinence in a true and full manner, not superficially. Desirable abstinence involves a gradual ascension, not a simple renunciation of pleasure. It means becoming spiritually fulfilled, harboring love for God, the Torah, and the commandments, while at the same time not lacking physical pleasure.
Finally, there is abstinence in the realm of conduct: separation from negative company. This does not mean cutting oneself off from the world, for "a man's mind should always be associated with his fellow men" (Taanit 7a). Rather, a person should associate with reputable persons for as long as may be necessary in the interest of Torah study and good deeds. The guiding rule is this: proper abstinence is that which does not weaken a person's positive inner faculties. Abstinence which weakens these faculties is undesirable.