The Ohr Hachaim Hakadosh and the Yetzer Hara

When discussing the insidiousness of the yetzer hara, Rav Shach, zt”l, would say: “The Makneh explains that when chazal say that one’s yetzer is renewed each day, this means that as one grows older his yetzer gets stronger and stronger. This is the meaning of the verse, "יצר לב אדם רע מנעוריו". From its youth, the yetzer naturally gets worse and worse. Now we can understand the words of the Mishnah at the end of Kinim: “The older an ignoramus gets, the more foolish he becomes.
“Rav Shach would explain, “This does not mean that one literally has a new yetzer each day, since with what new action can a yetzer entice a very old man? This means that since one has a yetzer from a young age and has done nothing much to combat it, it becomes an eighty year old yetzer. If the yetzer which is bad enough at twenty is left unchecked, what do you suppose he will be like at eighty?”
Interestingly, the Ohr Hachaim Hakdadosh, zt”l, learns an inspiring lesson from this seemingly bleak fact. “On Bava Kama 39 we find that an ox that is trained to gore in a stadium is not put to death for goring a man to death. This is learned from the phrase "כי יגח"—‘if he will gore’—on his own, but not if others force him to gore. Similarly, a man has a yetzer from the moment he emerges from the womb, way before he has enough understanding to be disgusted by evil. His yetzer leads him from the beginning. By the time he is grown up he is already used to doing evil, much like the goring ox is used to attacking. Like the ox, it is not entirely his fault. But although this point diminishes the punishment, a man must not remain the same. Surely the difference between man and animal is that man can use his innate understanding to curb his desires and change!”