1. The history of the Rebbe’s Mivtza Tefillin campaign and its directives:
The Rebbe began his Tefillin campaign in the year 1967, a few days prior to the six-day war. The Rebbe dedicated a talk on that Shabbos Parshas Bamidbar for this Mivtza, and it was spread to Chassidim and people around the globe after Shabbos, to begin the campaign. Nonetheless, the idea of influencing nonobservant Jews to put on Tefillin was already publicly discussed by the Rebbi in the 1950s.
The reason for the campaign-Enter fear in the enemy: The verse states “And all the nations of the land will see that the name of Hashem is written on you and they will fear you.” The Sages state that this statement refers to the head Tefillin, as the head Tefillin contains two letters of the three-letter name of Shakaiy. This Talmudic dictum served as one of the main motivations behind the Rebbe’s Tefillin campaign which he began in 1967, just days before the six day war, in order to impose fear on the enemy. While the campaign began prior to the six-day war, the Rebbe continued to implore for the continuity of the campaign even after the war for the sake of his purpose, to enter fear and trepidation into the enemy so they are too afraid to attack. Likewise, the Rebbe personally wrote dozens of letters to private individuals and security organizations, especially commanders of the Israeli Army, to be careful to put on tefillin every weekday as a defense against the enemy through entering fear into them. In short, the Rebbe viewed the wearing of tefillin and the tefillin campaign as the most important frontline defense against the enemy. To one individual the Rebbe wrote that “certainly you are aware that I am fully engrossed [i.e. Ich Koch Zich] in Mivtza Tefillin.” To General Ariel Sharon, the Rebbe wrote: “I strongly hope that you are careful to put on tefillin every single weekday, as in your case this is not just a personal private mitzvah that you are fulfilling and is rather something that is for the benefit of the public. While I am fully aware of all of your preoccupation with military and security matters, nonetheless on the contrary, this itself is an even greater reason for why you should be careful in fulfilling this mitzvah of both the hand and head tefillin.”
Putting on tefillin with this intent: The Rebbe stated that when those who put on tefillin do so in the merit of the soldiers then this assists in granting a long life to the soldiers, and that the fear of the soldiers fall upon the enemy.
To assist fellow Jews in their behavior: In a talk in 1950, the Rebbe explained that influencing other Jews to put on Tefillin is relevant not only to that Jew’s personal relationship with G-d, but also to his behavior in society, and that a Jew can be prevented from entering into criminal activity, such as stealing, simply by putting on Tefillin which enters spirituality and morals into his heart. Accordingly, states the Rebbe, one cannot excuse himself from influencing another Jew by saying I am not G-d’s policeman, as in truth this matter is relevant to society and is included within Mitzvos of Bein Adam Lechaveiro.
Women: Although women are exempt from the mitzvah of tefillin, the Rebbe encouraged and even obligated women to take part in the campaign through influencing men to put it.
2. The opposition:
When the Rebbe first came out with his Tefillin campaign, it was met with opposition from some camps, and was questioned by some Rabbanim, due to different Halachic questions. Of these included:
- Isn’t it forbidden to perform a Mitzvah for the sake of a Segula purpose?
- How can you put Tefillin on them in the street if they can see immodest woman?
- How can they fulfill their obligation if they don’t know what’s inside the Batim, and are unaware of the existence of Parshiyos?
- How can you put on Tefillin onto Reshaim?
The Rebbe dedicated an entire talk to address these claims, prefacing, that although it is out of character for him to do so and enter into arguments, he felt that if he would not do so it would cause a weakening in the Mivtza. All in all, with time this Mivtzah has been adapted by other sects of Jewry, and receives the blessing of all Gedolei Yisrael, despite the initial questioning.
 See Sichos Kodesh 5727 2:122; Likkutei Sichos 6:271; 19:121; Igros Kodesh 24:350; 25:71; 26:173; Sefer Mivtzaim Kehilchasam [Shmuel Bistritzky] p. 25-74; Shulchan Menachem 1:110-125; Shevach Yakar; Mavo for Igros Kodesh Vol. 24 and 25, 26, 29
 Sichos Kodesh 5727 2:122
 Sichas Parshas Pinchas 5710, printed in Toras Menachem 1 p. 147
 Parsho Ki Savo 28:10
 Rebbe Eliezer Hagadol in Menachos 35b; Brachos 6a; See Rosh Halchos Tefillin 12
 See Rashi and Tosafus ibid
 See Sichas Parshas Bamidbar 24th Iyar, 5727, printed in Mivtzaim Kehalacha p. 26; See also Likkutei Sichos 6:271, printed in Shulchan Menachem 1:110
 See dozens of letters in Igros Kodesh volume 24-26, including a letter to Rav Shteizaltz, Police force of Afula, Chief Rabbi of London, Rav Zeevin,
 Letter 9757, in volume 26 of Igros Kodesh
 Igros Kodesh 26:452
 Sichos Kodesh 5727 2:122
 Sichas Parshas Pinchas 5710, printed in Toras Menachem 1 p. 147, based on Gemara Shabbos 156b with Rebbe Nachman whose mother would make him wear a Yarmulka in order to educate him to have fear of heaven and not steal.
 Letter 11,171, in volume 29 of Igros Kodesh
 See Likkutei Sichos 6:271; Igros Kodesh 24:350; 25:71; Mavo for Igros Kodesh Vol. 24; Mivtzaim Kehilchasa p. 46; Shulchan Menachem 1:110-125
 See Likkutei Sichos 19:121 and letter 1230 that although one must fulfill Hashem’s decrees like a servant, irrelevant to the reason why he was commanded to do them, nevertheless, one can also have in mind to fulfill the Mitzvah of Hashem to protect him. Furthermore, even one who does a Mitzvah to bring him protection, although this is considered that he is doing the Mitzvah for an ulterior motif [lo lishma], nevertheless he has still fulfilled the Mitzvah. Regarding that which the Rambam writes [that one who writes names of angels on the Mezuzah to add in protection is considered a fool, and has lost his portion in the world to come being that he turned G-d’s command into a personal pleasure] this was only said in that case, being that they have proven by adding angels to the Mezuzah that they don’t believe that it’s the Mitzvah that protects, but rather think that it is a good luck charm and thus are considered heretics. [Likkutei Sichos ibid]
 See Igros Kodesh 14:52 and Chapter 5 Halacha 16
 See correspondence with Rav Yitzchak Hutner printed in Menachem Meishiv Nafshi, under his name and Chapter 2 Halacha 3 in footnotes, and in Shulchan Menachem 1:119-124
 See Mivtzaim Kehilchasam [Shmuel Bistritzky] p. 25-74; Chapter 1 Halacha 6