Should the chazan repeat the word emes?

The Midrash states that saying the 248 words of Kriyas Shema can heal a person's 248 body parts. There are, however, only 245 words in Shema. As a solution to this problem, the chazan repeats the words Hashem Elokeichem emes. Since he is motzei the tzibur, it is as if everyone said all 248 words. Some poskim hold that the chazan should not say the word emes when he is saying Shema to himself. Shulchon Aruch disagrees, maintaining that the word emes should be repeated. Some later poskim offer a compromise:  If the chazan must wait for the tzibur to finish, he should say emes. If there is no need to wait, he should not say emes.  

סעיף ג וס"ק ו ו־ח; ביאורים ומוספים דרשו, 4

How can an individual reach 248 words of Shema?

A person who is davening by himself does not have a chazan to complete the necessary word count. Shulchon Aruch says that a person in this situation should keep certain numerical calculations in mind when saying the brocha of V’yatziv. Rema offers another option of saying the words Kel Melech Ne’eman just before Shema. These three additional words bring him to the count of 248. If a person already said Shema before davening along with the words Kel Melech Ne’eman, the poskim disagree about whether he should say it again when he says Shema with the brochos.

סעיף ג; ביאורים ומוספים דרשו, 9

Should one stop in the middle of Shema to hear the chazan say Hashem Elokeichem emes?

Some Achronim say that if a person is still in the middle of Shema when the chazan is done, he should stop and listen to the chazan say Hashem Elokeichem Emes. Some add that even if he knows from the onset that he will not complete Shema with the chazan, it is better to listen to the chazan instead of adding the words Kel Melech Ne’eman. Other Achronim say that according to the teachings of Kabbalah, one should not stop in the middle of saying Shema.

ביאורים ומוספים דרשו, 6

• As we have learned, there is a disagreement in the Gemara about whether mitzvos tzrichos kavanah-- whether intent is necessary to fulfill a mitzvah. Shulchon Aruch rules according to the stringent opinion. Therefore, if one does a mitzvah without the proper intent, he must redo the mitzvah. In deference to the opinions which hold that one was already yotzei, a brocha is not recited the second time.

• If a person performed a mitzvah without proper intent, but the circumstances under which he did the mitzvah indicated that a mitzvah was being done, he fulfilled his obligation.

• Aside from one’s intention to be yotzei the mitzvah when saying Kriyas Shema, one must also have special kavanah when saying the first pasuk. 

• Can a daled be extended?

• What is an improper way to shake one’s head?

• Is repeating Shema ever permitted?