1) TEFILIN AND THE WINGS OF THE DOVE
QUESTION: The Gemara relates how the Tefilin of a man named Elisha miraculously turned into the wings of a dove when he was accosted by a Roman official during a period of persecution. (Some point out that the miracle was that his Tefilin appeared in the eyes of the Roman official to be the wings of a dove; see Machatzis ha'Shekel OC 28:4.) The Gemara explains that they became wings of a dove, because just as the wings of a dove protect the dove, so do the Mitzvos protect the Jewish people.
Why is the concept that the Mitzvos protect the Jewish people mentioned specifically with regard to the Mitzvah of Tefilin?
ANSWERS:
(a) The Gemara in Berachos (6a) says that the verse, "All the nations of the world will see that the name of Hash-m is called upon you, and they will be in awe of you" (Devarim 28:10), refers to the Tefilin Shel Rosh. We learn from there that the Tefilin protect us by causing the nations to fear us.
The mechanism for this effect may be as follows. One may not take his attention away from the holiness of Hash-m's name (which is written in the Tefilin) while he wears Tefilin (Yoma 6b). Therefore, one constantly focuses on Hash-m's Presence while he wears Tefilin. We learn from the Mishnah in Rosh Hashanah (29a) that when a person focuses on Hash-m's Presence, he can conquer all enemies and merit Hash-m's salvation ("v'Chi Yadav Shel Moshe..."). Similarly, when one wears Tefilin and focuses on Hash-m, he merits Hash-m's protection. (M. KORNFELD; see also Insights to Sotah 44:3, and Parasha Page, Lech Lecha 5757.)
(b) TOSFOS (49a, DH Kanfeha) explains the Gemara differently. According to Tosfos, the dove does not fight with its wings, but rather its wings protect it in the following way. Birds may be overcome by predators when they are at rest, but not while in flight. The dove is able to rest one wing at a time while it stays airborne with the other wing; it does not need to rest on the ground. In that way, its wings protect it. Similarly, when the Jews are not performing one Mitzvah, they are performing another Mitzvah. (See Menachos 29b, with regard to David ha'Melech, who, when in the bathhouse, was distressed that he was bereft of Mitzvos, until he noticed his Milah...").
This concept may be related specifically to Tefilin as follows. The Gemara and Rishonim state that Elisha removed only his Tefilin Shel Rosh. Apparently, he did not remove his Tefilin Shel Yad because the official could not see that he was wearing Tefilin on his arm, since the Tefilin Shel Yad are worn under the garment, and are not exposed like the Tefilin Shel Rosh. In this sense, the analogy to the wings of a dove is accurate; Elisha was still "flying" with one wing, so to speak, while resting the other, since he was still wearing the Tefilin Shel Yad even when he was forced to remove the Tefilin Shel Rosh!
It should be noted that the RITVA (49a) writes that this Gemara is the source for the manner in which we wrap our Tefilin Shel Rosh. We wrap the straps of the Shel Rosh around either side of the Tefilin, so that they form the shape of "wings of a dove." (This custom is also cited by the MAGEN AVRAHAM (OC 28:4) in the name of the MATEH MOSHE; see also MISHNAH BERURAH (OC 28:9).)
2) MITZVOS THAT THE JEWISH PEOPLE "STILL" ACCEPT WITH SIMCHAH
QUESTION: The Gemara states that any Mitzvah which the Jewish people originally accepted with Simchah, such as the Mitzvah of Milah, they still accept with Simchah.
Why does the Gemara emphasize that they still accept it with Simchah? Why should they not accept it with Simchah? Similarly, why does the Gemara emphasize that any Mitzvah which the Jewish people accepted with strife, they still accept with strife?
ANSWER: The VILNA GA'ON (Divrei Eliyahu) explains that according to the Gemara in Nidah (31b), the reason the Torah commands that a son be circumcised on the eighth day is because on that day the parents experience a great increase in their joy, since the seven days of Tum'as Leidah have passed and they can once again be together. Nowadays, the practice is not to observe the days of Dam Tohar, but rather to wait until any flow of Dam has ceased and then to count seven clean days. Accordingly, a husband and wife can never be together on the eighth day after birth. Nevertheless, the Gemara tells us that they still perform the Mitzvah of Milah with Simchah!
Similarly, the Jewish people initially accepted the laws governing immoral relations with relatives with dispute and strife, because at that time people had a strong Yetzer ha'Ra for marital relations with their relatives (see Insights to Yoma 75:1). The Gemara tells us (Yoma 69b), however, that this Yetzer ha'Ra was eradicated by the Anshei Keneses ha'Gedolah. Nevertheless, the Jewish people still accept the laws of marriage only with dispute.

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