The Shulhan Aruch (Orah Haim 146, and again in 285) writes that it is permissible, strictly speaking, to read "Shenayim Mikra Ve’ehad Targum" during the Torah reading. This refers to the obligation to read the weekly Parsha twice and its translation once. Although Halacha generally forbids speaking or learning during the Torah reading, one is permitted to read "Shenayim Mikra" during the Torah reading, since it is relevant to the reading. Nevertheless, the Shulhan Aruch adds (in Siman 146) that it is preferable only to read along with the reader to complete one of the two readings of "Shenayim Mikra," rather than read the Parsha twice and the translation during the congregational reading. Accordingly, Hacham Ovadia Yosef (in Yehaveh Da’at) and Hacham Bension Abba Shaul (in Or Le’sion, vol. 2) write that one should not read "Shenayim Mikra Ve’ehad Targum" during the Torah reading, but one may read along with the reader to fulfill one required reading, and conduct the other readings at some other point.
The most preferred way to fulfill this obligation, as Hacham Ovadia writes in his Halichot Olam, is to read each verse twice followed by its translation. If time is short, one may read once along with the reader, and then read the Parsha again followed by the translation, as discussed.
Preferably, one should complete the reading of "Shenayim Mikra Ve’ehad Targum" before he prays Minha on Shabbat afternoon. If one did not complete the reading by that time, then he can complete it until the reading of Parashat Bereshit on Simhat Torah.
Although there are some opinions that one should not study Targum (the translation of the Torah) at night, Hacham Ovadia rules that one is allowed to read "Shenayim Mikra Ve’ehad Targum" at night.
Rav Haim Palachi (Turkey, 1788-1869) warns that one should not read "Shenayim Mikra Ve’ehad Targum" as though it is a heavy burden of which he seeks to relieve himself. Rather, one should read the material slowly and carefully, in an attempt to enhance his understanding of the Torah text.
If a teacher teaches the weekly Torah portion in school, and during the course of his work he reads the Parasha twice, this suffices for the two readings required for "Shenayim Mikra Ve’ehad Targum," and he must then read only the Targum to fulfill his obligation.
The Ben Ish Hai (Rav Yosef Haim of Baghdad, 1833-1909), in Parashat Lech-Lecha, writes that it is preferable to read "Shenayim Mikra Ve’ehad Targum" on Friday, as this is part of one’s preparations for Shabbat. Nevertheless, as Hacham Ovadia notes, one who does not have time to do the entire "Shenayim Mikra Ve’ehad Targum" reading on Friday may do so earlier in the week.
The Ben Ish Hai also writes that it is preferable to conduct the entire "Shenayim Mikra Ve’ehad Targum" reading all at once, in a single sitting, without any interruption. Nevertheless, one may get a drink and recite "She’hakol" during the reading if he feels thirsty. Likewise, if a Rabbi is reading "Shenayim Mikra Ve’ehad Targum" and he is approached with a Halachic question, or is asked to deliver a class, he may certainly interrupt his reading. Otherwise, however, it is preferable to conduct the entire reading without any interruptions. The Kaf Ha’hayim (Rav Yaakob Haim Sofer, Baghdad-Israel, 1867-1939) writes that we create angels by reading "Shenayim Mikra Ve’ehad Targum," and by interrupting in the middle of the reading, we cause these angels to be blemished.
Reading "Shenayim Mikra Ve’ehad Targum" is a "Segula" for long life. However, as with all Misvot, we should perform this Misva in order to fulfill G-d’s will, and to learn and acquire Torah knowledge, and not for the rewards.
The Ben Ish Hai writes that it customary to read the final verse of the Parasha an additional two times after completing "Shenayim Mikra Ve’ehad Targum." Some also have the custom of reciting "Mizmor Shir Le’yom Ha’Shabbat" and "Hacham Malach" after the reading.
The Rama (Rav Moshe Isserles of Cracow, 1525-1572) writes that it is customary to also read each week’s Haftara. Unlike the Parasha, however, the Haftara is read only once, and not twice, and not with the Targum. In a week before a Shabbat when a special Maftir and Haftara are read, such as Shabbat Rosh Hodesh, Parashat Shekalim and Parashat Zachor, one does not have to read the Maftir for "Shenayim Mikra Ve’ehad Targum," since those Pesukim are read on the week of the Parasha in which they appear. However, the Ben Ish Hai writes that in such a week one should read the Haftara of that week’s Parasha, even though that Haftara will not be read in the synagogue.
The Ben Ish Hai writes that one should read "Shenayim Mikra Ve’ehad Targum" for Parashat Vezot Ha’beracha on Hoshana Rabba.
