(a) always one sin
(b) always two sins
(c) “our” minhag
(d) two sins until Parshat Pinchas, one thereafter
The following link (http://hirhurim.blogspot.com/2008/05/yisachar-or-yisaschar.html) enumerates 5 different minhagim for the pronunciation of the various occurrences of Yisakhar/Yisaskhar, as follows.(a) always one sin(b) always two sins(c) two sins the first time (in Vayeitzei) and one thereafter(d) two sins until Pinxas, one thereafter(e) repeat both ways until Pinxas, one sin thereafter.Explanations (in some cases two of them) are provided for all of these minhagim except (c), which is stated (in a single sentence, without any reason or justification) as a widespread custom. Well, (c) is at least "widespread" enough to have reached me in practice --- it was taught to me almost 50 years ago by the teacher who had the most influence on my leining education, and this is the way I have done it ever since. Does anybody have an explanation for this "widespread" custom? Also, are there any other minhagim out there besides the five that are listed above?
Quoting Shnayer Leiman below, you will find an explanation:
I. Several postings in recent weeks presented information on how a
particular rabbi or community pronounced the name "yissakhar." Such
information, while certainly welcome, is not without its drawbacks. While
the reader learns about yet another tree, he (she) gets no sense of the
forest. Ultimately in halakhah one must give weight to various opinions,
and not merely list them. Knowing the contours of the forest helps place
the significance (or: insignificance) of a particular tree in proper
perspective. It may be useful, then, to offer a concise survey of the
evidence from antiquity to the present. Concise, but not exhaustive, for
the MJ format and my limited knowledge of the sources do not allow for
every base to be touched. Hopefully, enough bases will be touched so that
the contours of the forest will begin to emerge.
II. The early authorities (rishonim) knew nothing about a dual
pronunciation of yissakhar (for which see below, section V). It was read
consistently (in the Torah) with one pronunciation only. The authorities
differed as to what this pronunciation was. The best attested readings and
pronunciations (in the various masoretic handbooks and vocalized biblical
manuscripts) are:
1. yissakhar (Dagesh in first sin; kametz under first sin;
second sin not pronounced.)
2. yisakhar (No dagesh in first sin; kametz under first sin;
second sin not pronounced.)
3. yisakhar (First sin not pronounced; kametz under second
sin; no dagesh in second sin.)
4. yissakhar (Both sins pronounced; first sin has quiescent
sheva under it; second sin has kametz under it.)
5. yishsakhar (First letter after yod is shin with quiescent
sheva under it; the shin is followed by a sin with
kametz under it.)
6. yisaskhar (Both sins are pronounced; patah under first sin;
quiescent sheva under second sin.)
III. There is evidence for other pronunciations in the early
period, but these are textually uncertain or not attested in the
biblical manuscripts, hence not listed here. Regarding the
pronunciations listed above (section II), some differ significantly from
each other, and some differ only slightly. Some differ not at all, but
simply reflect different methods of graphically noting the same
pronunciation of yissakhar. What needs to be noticed is that no early
authority suggested a dual pronunciation of yissakhar, and no early
authority knew of a pronunciation:
yisaskhar (Both sins pronounced; kametz under first sin;
quiescent sheva under second sin.)
IV. The Aleppo Codex and many other vocalized biblical
manuscripts ascribe to Ben Asher pronunciation 1 listed above. All
Sefaradim and Yemenite Jews follow this pronunciation. R. Meir ha-Levi
Abulafia (d. 1244), known as the Remah, in his Masoret Seyag la-Torah
(Florence, 1750, p. 71b) and R. Yedidyah Shlomo Norzi (d. 1616) in his
Minhat Shai (Vienna, 1814, p. 8b) to Gen. 30:18 rule that this is the
correct pronunciation. In the light of the apparent Ben Asher, Remah,
Minhat Shai coalition, pronunciation 1 is clearly the preferred
pronunciation for anyone who has no particular kabbalah on this
matter. Indeed, a host of later authorities (see below, section VII)
would rule that the Ben Asher, Remah, Minhat Shai coalition overrides
any and all particular minhagim, however entrenched they may be.
V. The later authorities added the following practices and
pronunciations to those listed previously in section II:
7. yisaskhar always
(Both sins pronounced; kametz under first sin;
quiescent sheva under second sin.) First attested:
nineteenth century (see, e.g., Bet Aharon
ve-Yisrael 3:5[1988], p. 133, note 40).
8. yisaskhar first time only
(At Gen. 30:18 pronounced as pronunciation 7; from
then on pronounced as pronunciation 1.) First
attested: seventeenth century (see, e.g., R. Yair
Hayyim Bacharach [d. 1702], Mekor Hayyim, Jerusalem,
1984, vol. 2, p. 207).
9. yisaskhar throughout Genesis
(In Genesis pronounced as pronunciation 7; from
then on pronounced as pronunciation 1). First
attested: nineteenth century (see, e.g., R.
Eliezer Auerbach, She'elot u-Teshuvot Tur ha-Even,
Paritsk, 1818, number 8, end).
10. yisaskhar until parashat Pinhas
(From Gen. 30:18 through Numbers 26:22 pronounced
as pronunciation 7; from Numbers 26:23 on pronounced
as pronunciation 1.) First attested: seventeenth
century (see, e.g., R. Ya'akov Zaslover,
Nahalat Ya'akov, Sulzbach, 1686, pp. 21a and b).
11. yissakhar and yisaskhar
(From Gen. 30:18 through Numbers 26:22 each verse
containing yissakhar is read twice, once with
pronunciation 1 and once with pronunciation 7; from
Numbers 26:23 on each attestation is pronounced
only as pronunciation 1.) First attested: twentieth
century (see, e.g., R. Hershel Schachter, Nefesh
ha-Rav, Jerusalem, 1994, p. 308; the claim
here that these verses were repeated twice in
Volozhin is not attested in earlier literature).
VI. Each of the practices and pronunciations of the later
authorities -- none of which is mentioned by the earlier authorities --
can be defended with difficulty. All are attempts to come to grips with
one or more of the following issues:
1. A basic rule of masoretic Hebrew is that one never pronounces
a letter (except at the end of a word) which has no masoretic
vocalization. The second sin in yissakhar -- in present Bibles -- has
no masoretic vocalization. On the other hand, the word yissakhar does
not appear on any authentic masoretic list of "qere ve-ketiv." [The
masoretic note in the Netter Bible at Gen. 30:18 is mostly imaginary, as
is well known to experts in Masorah.] This led to the conclusion that at
least once (and perhaps always) yissakhar needs to be pronounced
yisaskhar.
2. In order to account for the change in name of Yissakhar's son
from Yov (Gen. 46:13) to Yashuv (Nu. 26:24), R. Eleazar of Worms
(d. 1230) in Rokeah 'al ha-Torah, Bnei Brak, 1978-1981, vol. 3, p. 113,
and Tosafot (12th - 14th centuries) in R. Ya'akov Gellis, ed., Tosafot
ha-Shalem, Jerusalem, 1984, vol. 3, p. 162, explain that Yissakhar
donated his superfluous shin/sin to his son Yov, thereby changing his
name to Yashuv. Note that neither the Rokeah nor Tosafot claim that this
explanation in any way calls for a change in the pronunciation of the
name yissakhar. When did the name change occur? If shortly after Yov's
birth or during his early childhood (see, e.g., R. Shimeon Auschenburg,
Devek Tov, Venice, 1588, p. 108 , the superfluous shin/sin belonged to
Yissakhar only at Gen. 30:18 and for a short while thereafter. If so, it
was felt by the later authorities that one pronuciation of the two sins
of Yisakhar (at Gen. 30:18) would do admirably. Others later authorities
said, however, that the names Yissakhar and Yov appear together at Gen.
46:13; surely, here too it must be pronounced with two sins! Thus, the
change was best reserved for the beginning of Exodus, where the
progenitors of the twelve tribes died. After all, Yissakhar must have
donated the superfluous shin/sin before he died. Still others maintained
that the spelling Yashuv first occurs in Nu. 26:24; until that point,
then, all mention of Yissakhar is to be pronounced with double sin.
3. Precisely because of the confusion, better to repeat than
err. The Rav (see pronunciation 11), in order to be on the safe side,
read the verses containing yissakhar twice, with two different
pronunciations, until Nu. 26:24 where virtually all agree (except Dinov,
Munkatch, Stolin-Karlin, and others) that pronunciation 1 is the only
correct one.
4. Several sources (uniformly late) stress that two sins (or:
double sin) are to be pronounced. In all likelihood, what was intended
was that the dagesh in the first sin be noted, together with its impact
on the pronunciation of yissakhar. This was misunderstood by some to
mean that the proper pronunciation of the name is yisaskhar or (even)
yisasakhar. See, e.g., the comments of R. Eizekel of Komarno,
referenced below in section VII.
VII. Leading eighteenth and nineteenth century halakhists and
masoretic scholars were dismayed by these developments and called for a
return to the Ben Asher, Remah, Minhat Shai coalition which recognized
pronunciation 1 as the only correct one. Among those calling for such a
return were: R. Solomon Zalman Hanau (Sha'arei Tefillah, Jassnitz,
1725); R. Eliyahu b. Azriel of Vilna (Mikhtav me-Eliyahu, Hamburg, 1738;
with a strong letter of approbation from R. Jacob Poppers, Chief Rabbi
of Frankfurt on the Main); R. Wolf Heidenheim (Torat ha-Elokim,
Offenbach, 1797; his liturgical and masoretic works were praised by
R. Moses Sofer; R. Solomon Dubno (Tikkun Soferim, Amsterdam, 1803; his
masoretic work received the warm support of R. Ezekiel Landau); R. Uri
Shraga of Dobrovno (Minhat Kalil, Dobrovno, 1804; his masoretic work
received the strong support of R. Hayyim of Volozhin); R. Eizekel of
Komarno (Heikhal ha-Berakhah, Lemberg, 1871; whose clever pun needs to
me mentioned here. Railing against those who do not take into account
the dagesh in the first sin of yissakhar, he claims that it was
concerning them that the Psalmist wrote [Psalm 63:12] "the mouth of
liars is stopped up [Hebrew, as popularly pronounced in some circles:
yisukher];") and R. Dov Baer Reifmann (Shulhan ha-Qeri'ah, Berlin, 1882;
this halakhic guide to the rules and regulations governing Torah scrolls
and their public reading has letters of approbation from the brothers
R. Shlomo and R. Bezalel ha-Kohen of Vilna, from R. Azriel Hildesheimer
of Berlin, and from the Chief Rabbi of Tyrnau in Hungary). Apparently,
the call fell largely on deaf ears.
VIII. In sum, pronunciations 7-11 are of recent vintage. Each
can be justified and has its enthusiastic adherents. Whether Leah (who
invented the name), Yissakhar (the first to bear it), the talmudic
rabbis, or the medieval masoretes would have looked kindly on these
pronunciations is a matter perhaps best left for historians and
linguists.
Shnayer Z. Leiman\ 11. yissakhar and yisaskhar (From Gen. 30:18 through Numbers 26:22 each verse containing yissakhar is read twice, once with pronunciation 1 and once with pronunciation 7; from Numbers 26:23 on each attestation is pronounced only as pronunciation 1.) First attested: twentieth century (see, e.g., R. Hershel Schachter, Nefesh ha-Rav, Jerusalem, 1994, p. 308; the claim here that these verses were repeated twice in Volozhin is not attested in earlier literature). 3. Precisely because of the confusion, better to repeat than err. The Rav (see pronunciation 11), in order to be on the safe side, read the verses containing yissakhar twice, with two different pronunciations, until Nu. 26:24 where virtually all agree (except Dinov, Munkatch, Stolin-Karlin, and others) that pronunciation 1 is the only correct one.----------------------------------------------------------------
Don't argue with Ari. He is just quoting Leiman, who cites Nefesh
Harav, both of whom are reliable enough to cite (which is not to say
your memory is wrong.) Do you know/recall what the Rav was leining out
of for the haftarah -- Klaf, sefer or haftarah book?