A question arises in the case of one who has reached somewhere around the point of "Modim" in his Shemona Esre prayer on Chanukah when the Chazan begins the repetition of the Shemona Esre. Should a person in this situation skip the recitation of Al Ha'nisim and Bi'mei Matityahu, which we add during Chanukah, in order to be able to recite Nakdishach with the congregation? Since one may not recite Nakdishach while he is still in the middle of Shemona Esre, we should perhaps advise such a person to skip the section added during Chanukah so that he can complete the Shemona Esre prayer by the time the Chazan reaches Nakdishach.
This possibility becomes more compelling in light of the position of Rav Chayim Vital (famous disciple of the Arizal, late 16th century, Tzefat) that the recitation of Nakdishach constitutes a Torah obligation. Since the recitation of Al Ha'nisim on Chanukah is clearly a rabbinic obligation, perhaps one should forego on this recitation in favor of Nakdishach.
In truth, however, Halacha says that one should not skip Al Ha'nissim for the sake of reciting Nakdishach. For one thing, Rabbi Chayim Vital's position does not represent the mainstream view. Many Rishonim (Medieval Halakhic authorities), including the Ran, the Meiri, the Rosh and others, maintain that the obligation to recite Nakdishach is of rabbinic, rather than Biblical, origin. And although the Talmud does cite Biblical verses as the source for Nakdishach, these verses should be seen as but an "Asmachta" (an allusion in the Biblical text to a law enacted by the Sages, rather than the actual source of the Halacha).
In addition, the principle of "Osek Be'mitzva Patur Min Ha'mitzva" mandates that while a person is involved in a Mitzva, he need not concern himself with another Mitzva that comes his way or looms on the horizon. A person busy fulfilling one Mitzva should focus his attention on completing that Mitzva, and need not disrupt his performance for the sake of other Mitzvot. Therefore, when a person recites Shemona Esre on Chanukah and reaches Al Ha'nissim, how his recitation will affect the possible future obligation regarding Nakdishach need not concern him. Since right now he is faced with the obligation to recite Al Ha'nissim, he should proceed with this recitation, even at the expense of Nakdishach.
Precedent for this concept may be found in a ruling of the Ramban concerning a case of a Berit Mila performed on Shabbat. Halacha requires that the hot water needed for treating a baby after a Mila must be prepared before Shabbat. The Ba'al Ha'ma'or and the Ramban debate the question of what one should do if the hot water prepared before Shabbat spills. According to the Ba'al Ha'ma'or, since performing the Mila will give rise to a situation of Pikua'ch Nefesh (risk to life) requiring one to violate Shabbat by heating water for the baby, the Mila should be delayed until after Shabbat. The Ramban, however, maintains that the Mila should be performed, despite the fact that this will necessitate violating Shabbat to treat the infant. Since at this moment the obligation of Mila requires circumcising the baby, and only at that point will it become necessary to violate Shabbat to heat the water, we should proceed with the circumcision without concern for how this may affect a different Mitzva later on. Similarly, in our case, the individual should recite Al Ha'nissim without looking ahead to the repercussions of this recitation with respect to Nakdishach.
Rabbi Chaim Pinchas Scheinberg issued a similar ruling concerning the recitation of U’Be'sefer Hayim towards the end of Shemona Esre during the Aseret Yemei Teshuva (the period from Rosh Hashanah through Yom Kippur). Even though this insertion does not appear in the Talmud, and was instituted later, by the Geonim, nevertheless, Rabbi Scheinberg rules that one should not skip U’Be'sefer Hayim in order to complete Shemona Esre in time to recite Nakdishach. Since at this moment he is required to recite U’Be'sefer Hayim, he should fulfill this requirement without concerning himself with the future obligation of Nakdishach.
It should be noted that whenever an individual is in the middle of Shemona Esre when the congregation reaches Nakdishach, he should stand silently and listen to the Chazan's recitation of Nakdishach. After the Chazan recites the verse, "Yimloch Hashem Le'olam," the individual then proceeds with Shemona Esre.
Summary: One should not skip Al Ha'nissim and Bi'mei Matityahu in order to complete Shemona Esre in time to recite Nakdishach with the congregation. If he does not complete his Shemona Esre in time for Nakdishach, he should remain silent, listen to the Chazan's recitation of Nakdishach, and then continue his Shemona Esre.
