“The design of man’s heart is evil from his youth” (Bereishit 8:21)
Rashi explains that the words from his youth(מנעריו) is punctuated to read from the time that he stirs (מִנְעָרָיו). Thus it can be interpreted as, “From when he stirs to leave his mother’s insides, the urge to do evil is put in him.”
The Radak writes that his design is called Yetzer because it was created (נוצר) together with him. The Yetzer Hara enters a person before his Yetzer Hatov. One attains his Yetzer Hatov gradually, as the pasuk (Iyov 11:12) states, “Let the empty man acquire a heart! Let one who is like a wild ass be reborn as a man.” A person is born as a wild ass, without intellect. Later on in life, he progressively acquires a heart of goodness.
The Gemara says (Berachot 61a) in the name of Rav: The Yetzer Hara is compared to a fly, nestling between both chambers of the heart, as the pasuk says (Kohelet 10:1), “Dead flies putrefy the performer’s oil.”
The Gemara (Sanhedrin 91b) recounts an interesting exchange: Antoninus asked Rebbi, “When does the Yetzer Hara gain control over a person – from his conception or from his birth?”
Rebbi replied, “From his conception.”
“But he kicks in his mother’s womb, and emerges. Obviously, his Yetzer Hara comes only with his birth.”
Rebbi acquiesced to Antoninus’s assertion, basing his ruling on the pasuk (Bereishit 4:7), “Sin rests at the door.”
Rabbi Yitzchak Zev Soloveitchik writes (Chiddushei HaGriz Hachadashim 87) that the Gaon, Rabbi Yitzchak MiPetersburg states that these are two military tactics in our ongoing battle with the Yetzer Hara. Torah is a segulah, a form of remedy against the Yetzer Hara, which must be strictly adhered to in order to prove effective. Torah must be studied completely l’shem Shamayim. Conversely, remembering one’s day of death, i.e., the study of mussar, even if done minimally, is still beneficial.
When the Gaon, Rabbi Chaim, heard this, he disagreed. He says that Torah is compared to a condiment which is mixed into one’s food, and is a natural ingredient. Torah is not a segulah, but a natural means of averting the Yetzer Hara. He offers the following analogy:
A person who is afraid of catching cold will wear warm clothing before going outdoors, in order to avoid getting sick. But after getting sick, warm clothes alone won’t do the job. At that point, he must take medicine. Imagine if, when one is still healthy, he takes medicine before stepping outdoors, instead of bundling up with warm clothes. Not only will it not help him, it will make him sick.
Rabbi Chaim, ends with the following: Hashem created a destroyer in the form of the Yetzer Hara. The best advice in order for one to be spared from his ailments is to cleave to the Torah. But that is only as long as he has not yet been affected. Torah is the means by which one is protected from the machinations of the Yetzer Hara. But once a person has succumbed to the persuasions of the Yetzer Hara, the Torah alone is not effective. Remembering his day of death is the remedy necessary at this point.
The Chafetz Chaim expounds (Nevi’im 48): Every creature has some measure of fear. When it is chased away, it does not return immediately. But the fly is different. Even if it is chased away one hundred times, it will return tenaciously to its former place. This is the way of the Yetzer Hara. As the Ba’alei Mussar assert, “You sleep, yet he remains awake.” For this reason, our earlier Sages exhort that a person should always place his Yetzer Hara under his control, never believing he has conquered it completely.
