The Tur begins the first law of his noted work “Arba Turim” with a quote of the Mishneh in Avos. This Mishneh is a general description of the conduct a Jew is to emulate throughout his life. These matters to be listed are fundamental pillars in successful service of G-d which a Jew needs to imbue within his daily existence. It is for this reason that the Tur began the first section of his Daled Turim, which discusses the laws involved in a Jews daily conduct, with this statement, as prior to describing the details of one’s daily conduct one must first embed within himself the elementary skills needed to be successful in battling evil and performing good.
The Shulchan Aruch of the Michaber, in contrast to the Tur, does not quote the entire Mishneh and so follows the first edition of Shulchan Aruch Harav. However in the second edition [Mahadurah Basra] Admur inserted this Halacha written by the Tur as the first Halacha in the Shulchan Aruch.
Attributes that one should emulate throughout his life:
Rabbi Yehuda Ben Teima stated: One should be as bold as a leopard, as light as an eagle, as swift as a deer, and as strong as a lion in order to fulfill the will of your Father in Heaven. The following is the meaning of these attributes:
Be as bold as a leopard:
Sparks of Chassidus
In previous times, when persecution of Jews and Judaism was common, the Mesirus Nefesh in service of G-d was in the most literal sense, to give up one’s life to serve G-d. In current times where most Jews live in democratic countries which provide freedom of religion the Mesirus Nefesh required is on a different scale. One’s Mesirus Nefesh today involves not being affected by the words of scoffers and continuing his service of G-d despite the common public consensus which ridicules his method of life.
Moshe was humbled by our Mesirus Nefesh: The Alter Rebbe taught that the humility of Moshe which surpassed the humility of all other people was mainly affected by his foreseeing the challenges that the Jews in the time of the footsteps of Moshiach would face and succeed. When he saw the Mesirus Nefesh in which the Jews at that time would serve Hashem against all the concealments and public ridicule he became humbled in his own service.
 Avos 5/20
 He only makes mention of being strong like a lion to motivate one to awaken early. The other matters however were omitted.
 See next footnote.
 Mahadurah Basra 1/1 as writes Tur; omitted in Michaber; Rama; M”B
Ruling of Mahadurah Kama: In the first edition [Mahadurah Kama] Admur only mentions the matters of being like a lion to wake up early in the morning [1/1] and being like a leopard to not feel intimidated by scoffers [1/3]. The remaining matters of the Mishneh were omitted.
 As for the reason why the Sages stated to emulate the animals and did not simply state what one is to do, see Kuzari 3/5 that one is to find a lesson in service of G-d in all items that he is aware of. This follows a traditional teaching of the Baal Shem Tov [see Keser Shem Tov Miluim 223] that everything one hears or sees is a lesson in service of G-d. Perhaps for this reason the Sages taught us the fundamental services of G-d from the animals, in order to also emphasize the need to see everything in life as a message from G-d in how he is to be served.
 Basra 1/1; Kama 1/3; based on Tur brought in Rama 1/1
This is the first matter mentioned in the Mishneh being that it is a great component of service of G-d as at times one desires to do a Mitzvah and avoids doing so due to scoffers. [Tur] This is the foundation of all one’s service of G-d. [Toras Menachem 22 p. 38]
 Mahadurah Basra 1/1
 Mahadurah Kama 1/3; Lit. Az Kinemer.
 Mahadurah Kama ibid based on Beis Yosef; Ketzos Hashulchan 1 footnote 2
Mahadurah Basra: Admur omitted this Halacha in the second edition. Vetzaruch Iyun.
 Meaning one should not answer them in an ill mannered way. This implies that he may answer them in a polite method.
Answering back to Apikorsim: The Biur Halacha writes that Apikorsim which are coming to make changes in the status quo of Judaism, may be spoken to in a brazen manner if speaking to them politely does not affect them. One may conduct a full out war against them. Included in matters of Heresy are all matters that are opposed to Daas Torah. [Ketzos Hashulchan 1 footnote 2] To note however that while this was the path taken against the non-believers in previous generations, today society has changed and in majority of cases one accomplishes a lot more through respect and polite conversation than through offensive battles. This summarizes the focal point of the Chabad-Lubavitch movement of bringing Jews closer to Judaism through showing open love and acceptance to every Jew. Nevertheless when necessary the Rebbe promoted open battles against public matters that opposed Judaism although always differentiating between the people involved and their opinions.
 As doing so may cause one to become brazen even towards matters that are not dealing with service of G-d. [Kama ibid]
 Toras Menachem 3 p. 157; See also Mamar “Ein Hakadosh Baruch Hu Ba Betrunya” 5648 for a thorough overview of the Mesirus Nefesh required in today’s times against the scoffers. The Rebbe Rayatz instructed the students of Tomchei Temimim to commit this Mamar to memory. [Sefer Hamamarim 5685 p. 7]
 Mamar Yud Kisleiv 1941 [Mamarim Melukatim 2 p. 51]