Slaughtering in the North

The Alter of Kelm, zt”l, explained that honor is dangerous for even the greatest tzaddik. “It is clear from the command, 'והצנע לכת עם ה' אלוקיך'--'And walk humbly with Hashem your G-d'--that honor makes an impression on even the greatest person. It is human nature to willingly trade the eternal honor afforded to those who keep Torah and mitzvos for honor in this world—even honor bestowed by people of insignificant spiritual stature or even lacking worldly fame. A person is naturally drawn to do whatever it takes to get a little honor, even a heinous sin if necessary! It is for this reason that the verse must warn us to be as modest as possible in our avodah.”
“Rav Yisrael Salanter, zt”l, would always hide as much of his avodah as possible,” the Alter recounted. “The midrash regarding Shmuel HaNavi applies to him equally: ‘Look at this creation which I created in My world. All other humans work to magnify their name, while he toils to diminish his name.”
Rav Dovid of Skver, zt”l, learned just this behavior from a Mishnah we say during korbanos. “We say each day during davening, 'איזהו מקומן של זבחים? קדשי קדשים שחיטתן בצפון'. The Mishnah alludes to the best way to serve Hashem. It directs us that 'שחיטתן בצפון'. The best place to serve Hashem is to do whatever good he can and slaughter his evil impulses in צפון. In addition to meaning on the norther side this word also means hidden, as in צפון in the Haggadah. This teaches that specifically mitzvos done privately overcome our natural desire for honor, and they are in the category of kodesh kodashim. Precisely these mitzvos are the highest avodah.”