Megillah 23B

כנגדו נמי לא בעי.

it is not necessary to also add corresponding verses in the haftara.

מתקיף לה רבא: והרי ״עולותיכם ספו״, דלא הויין עשרין וחד, וקרינן! שאני התם, דסליק עניינא.

Rava strongly objects to this baraita: But there is the haftara that begins with the words: “Add your burnt offerings” (Jeremiah 7:21–28), which does not have 21 verses, and nevertheless we read it. The Talmud answers: There it is different, as the topic is completed in fewer than 21 verses, and it is not necessary to begin another topic merely to complete the number of verses.

והיכא דלא סליק עניינא לא? והאמר רב שמואל בר אבא: זמנין סגיאין הוה קאימנא קמיה דרבי יוחנן, וכי הוה קרינן עשרה פסוקי, אמר לן: אפסיקו! מקום שיש תורגמן שאני. דתני רב תחליפא בר שמואל: לא שנו אלא במקום שאין תורגמן, אבל מקום שיש תורגמן ⁠— פוסק.

The Talmud asks: But is it true that where the topic is not completed, we do not read fewer than 21 verses? Didn’t Rav Shmuel bar Abba say: Many times I stood before R' Yoḥanan as a translator, and when we had read 10 verses he would say to us: Stop. This indicates that a haftara need not be 21 verses. The Talmud answers: In a place where there is a translator, who translates each verse into Aramaic and adds additional explanation, it is different. In that case, it is not necessary for the haftara to consist of 21 verses, so as not to overburden the congregation, as Rav Taḥalifa bar Shmuel taught: They taught that 21 verses must be read from the haftara only in a place where there is no translator; but in a place where there is a translator, one may stop even before that.

מתני׳ אין פורסין על שמע, ואין עוברין לפני התיבה, ואין נושאין את כפיהם, ואין קורין בתורה, ואין מפטירין בנביא,

Mishnah: One does not recite the introductory prayers and blessing [poresin] before Shema; nor does one pass before the ark to repeat the Amida prayer; nor do the priests lift their hands to recite the Priestly Benediction; nor is the Torah read in public; nor does one conclude with a reading from the Prophets [haftara] in the presence of fewer than 10 men.