On the Shabbat before Rosh Hodesh Adar,1 which is followed by Nissan,
is Shabbat Parashat Shekalim.2
If Rosh Chodesh [Adar] falls on Shabbat,
then that (Shabbat and Rosh Hodesh) would be Shabbat Shekalim.
One would (in that case) take out three Torah scrolls.
From the first (scroll) six (people) are called up for (the reading of) the weekly portion.
From the second (scroll) the seventh (person) reads (the passage) for Rosh Hodesh
and we begin from ''And on the sabbath day''3
and (then) say half-kaddish.
From the third (scroll) one reads (as) Maftir from Parashat Shekalim,
and (for) the Haftorah (from the special one for) Shekalim.4
If one made a mistake and started to read first from Parashat Shekalim,
one (does not stop but) finishes (the reading).
The Maftir (then) reads from the (reading for) Rosh Hodesh,
then the Haftorah is also that of Shabbat and Rosh Hodesh.1) In a leap year, this refers to the second month of Adar.
2) Four different passages from the Torah are each read on specific Sabbaths in addition to the regular weekly Torah readings, each passage having themes which relate to the months of Adar and Nissan. Parashat Shekalim (Exodus 30:11-16) is the reading which describes the donation of the half-shekel.
While the Beit Hamikdash stood, each person was obliged to donate a half shekel every year to the Temple. The donations were used to purchase the animals for the communal sacrifices. From Rosh Chodesh Nissan onwards, all the communal sacrifices had to be purchased using money collected that year. Therefore, one month before, on Rosh Chodesh Adar, announcements would be made to remind people to donate the half-shekel, so that animals could be purchased with the ''new'' money before Nissan. The reading of Parashat Shekalim just before (or on) Rosh Chodesh Adar serves as a reminder of that mitzvah.
3) Also see Ch. 78:1 and Ch. 79:1.
4) II Kings 11:17.
שבת שלפני ראש חדש אדר הסמוך לניסן
הוא שבת פרשת שקלים
ואם חל ראש חדש בשבת
אזי הוא שבת שקלים
ומוציאין שלשה ספרי תורה
בראשון קורין ששה בפרשת השבוע
בשני קורין השביעי בשל ראש חדש
ומתחילין וביום השבת
ואומרים חצי קדיש
בשלישי קורין מפטיר בפרשת שקלים
ומפטירין הפטרת שקלים
ואם טעו והתחילו לקרות תחלה בפרשת שקלים
גומרים
והמפטיר קורא בשל ראש חדש
ומפטיר גם כן הפטרת שבת וראש חדש On the Shabbat before Purim (we read) Parashat Zachor.1
On the Shabbat before Rosh Hodesh Nissan (we read) Parashat HaHodesh.2
If Rosh Hodesh (Nissan) falls on Shabbat,
then that becomes Parashat HaHodesh,
and its rules are as the case (see above) of Rosh Hodesh Adar that falls on Shabbat.
On the Shabbat which is before (that of) Parashat HaHodesh (we read) Parashat Parah.31) Deut. 25:17-19) - which contains the commandment to recall the attack of the nation of Amalek which occurred just after the exodus from Egypt.
2) Exodus 12:1-20 - which describes the mitzvah to sanctify the new moon and the mitzvah to offer the ''Korban Pesach'' - Passover offering - on the afternoon of the fourteenth of Nissan.
3) Numbers 19:1-22 - which describes the purification ceremony of those who are ritually impure due contact with a human corpse.
שבת שלפני פורים הוא פרשת זכור
והשבת שלפני ראש חדש ניסן הוא פרשת החדש
ואם חל ראש חדש בשבת
אז הוא פרשת החדש
ודינו כמו ראש חדש אדר שחל בשבת
והשבת שלפני פרשת החדש הוא פרשת פרה Some (authorities) say that Parashat Zachor and Parashat Parah
are required to be read from the Torah.1
(For this reason) a child (under 13 years old) should not read these (Parashiot).2
Similarly, people (living) in (small) villages who do not have (ten adult males) a Minyan,
need to go to a place where (they can read because) they have a Minyan.
If this is impossible for them,
at the very least, they should read (these passages) with the proper (cantillation) notes.1) Most later authorities rule that the reading of Parashat Parah is a rabbinical mitzvah, not a Biblical one - see Mishna Berura 685:15.
2) The reader must be obliged by Torah law to read these, so that the congregation is covered by his reading. The child under 13 years old, does not have a Torah obligation (on any commandments) and therefore cannot cover any one else.
יש אומרים כי פרשת זכור ופרשת פרה
חייבים לקרותם מדאורייתא
ואין קורין בהם קטן למפטיר
ובני הישובים שאין להם מנין
צריכין שיבאו למקום שיש מנין
ואם אי אפשר להם
לכל הפחות יקראו אותן בנגינות כראוי