Completing a point from the previous shiur: defining "tadir" regarding sefiras ha'omer and kiddush levanah

Shulchan Aruch, siman 489, se'if 9
"On Friday night and on the night of Yom Tov we recite the blessing and count after the kiddush that is made in shul, and on the night following Shabbos or Yom Tov we count before havdalah."
(Shulchan Aruch)

Completing a point from the previous shiur: defining "tadir" regarding sefiras ha'omer and kiddush levanah

The rule: When one mitzvah is tadir (more frequent) and another is not, the more frequent one comes first. The question is what exactly qualifies as "tadir," and one of the classic examples is the relationship between sefiras ha'omer and kiddush levanah.
The side that sefiras ha'omer is more frequent: Sefiras ha'omer is performed every single day, and from that perspective it is more frequent, even though it is limited to a short stretch of the year.
The side that kiddush levanah is more frequent: Kiddush levanah is performed twelve times a year, spread across the entire year, and from that perspective it should be viewed as the tadir one.
A dispute among the Acharonim: The matter is disputed among the Acharonim, and this is one more example of the debate over how to define "tadir."
The practical ruling: Most poskim held that one first counts the omer and only afterwards says kiddush levanah, and this is independent of the whole tadir question: kiddush levanah is certainly only a rabbinic obligation, whereas sefiras ha'omer nowadays may be a Torah obligation and may be rabbinic, and it is part of the order of the tefillah.

The order of the counting on Friday night and on the night of Yom Tov

The question: Why is the counting done after the kiddush recited in shul and not before it? One answer given is the frequency of kiddush, which comes around every week, as opposed to sefiras ha'omer, which applies only during a particular period.

"After the kiddush in shul: because whatever we can do to bring in the sanctity of the day earlier, we should do."
(Mishnah Berurah)

The Mishnah Berurah's reasoning: Even though the sanctity of Shabbos has already been accepted in the tefillah, kiddush is what marks the entry of Shabbos, and therefore we place it before the counting.
The idea behind it: Our affection for Shabbos. A person wants to bring its arrival forward as much as he can, and therefore he says kiddush before sefiras ha'omer.

One who counts at home

"But if he is counting at home, he should count before kiddush."
(Mishnah Berurah)

The reason: One may not eat before fulfilling the mitzvah, and therefore at home, where the kiddush is the kiddush that precedes the seudah, he must count first and only then make kiddush.
The difference from the kiddush in shul: The kiddush made in shul was instituted for guests, not for the person himself, so there is no clash there between kiddush and eating.

The reason for the prohibition to eat before fulfilling a mitzvah

Lest he forget: Any mitzvah whose time begins at tzeis hakochavim (nightfall) may not be preceded by eating or by involvement in other matters, out of concern that the eating or the activity will cause him to forget to perform it.
Krias Shema at bedtime: This is no contradiction, since the obligatory Krias Shema was already recited in Maariv before the meal. Krias Shema at bedtime is by its very definition the reading said before going to sleep, and its place is therefore after the meal.

The order of the counting at the conclusion of Shabbos and Yom Tov

"Before havdalah: because we push off the departure of the day as much as we possibly can."
(Mishnah Berurah, s.k. 40)

The rule: Just as we bring the acceptance of Shabbos forward, so we delay its departure. Therefore we first count the omer and push havdalah off as far as possible, and in shul havdalah is the last thing done at the conclusion of Shabbos.
The familiar expression: One who hurries to accept Shabbos delays leaving it, as we say in the Shabbos zemiros: those who delay in leaving Shabbos and hurry to bring it in.
The point of it all: In every way possible we should show how beloved Shabbos Kodesh is: bringing it in early and seeing it out late.

Background: the structure of the Shulchan Aruch and the divisions of the Tur

Orach Chaim: The section we are learning here together with the Mishnah Berurah. It deals with berachos, tefillos, the reading of the Torah, the conduct of the shul, and also the meals eaten at home and the berachos that come around from time to time.
Yoreh Deah: The second section, and the most complex of them all.
Even Ha'ezer: Its name is drawn from the verse "I shall make him a helper corresponding to him," and it deals with all matters relating to women: gittin, kesubos, yevamos and the like.
Choshen Mishpat: It deals with the laws between one person and another, including the laws of damages.
Who established this division: Rabbi Yaakov ben Asher, the Baal HaTurim, who authored the four Turim. On them Rabbi Yosef Karo wrote his major work, the Beis Yosef, containing all the sources and explanations. Since the material grew so vast that no one could finish it, he abridged it, and that abridgement is the Shulchan Aruch.
Following the order of the Tur: The Shulchan Aruch is not an entirely independent work; it follows the order of the Tur. Therefore if you open the Tur at siman 489 you will find more or less the same halachos, with the Shulchan Aruch's additions. And since the Tur is divided into four sections, the Shulchan Aruch too is divided into four sections.
No connection to the Rambam's arrangement: The division is not based on the Rambam, whose work is built of fourteen books in an entirely different arrangement. The Baal HaTurim's division is his own.

The character of Yoreh Deah

Its opening is well defined: What is missing from all the other sections is the laws of kashrus, the Jewish table and the Jewish kitchen. Yoreh Deah therefore opens with the laws of shechitah, and after them meat and milk, tereifos, eggs, blood and everything connected to eating: roughly a hundred simanim.
Its conclusion: The laws of honoring a sefer Torah, mezuzah, honoring parents, honoring talmidei chachamim, and the laws of aveilus.
The middle: The laws of the mitzvos that apply to the land, even though the author sat in Spain. Some have called this the laws of Eretz Yisrael. He wrote only a little about them, perhaps as a remembrance of the matter and on account of rabbanim who went up to the Land.
Appendices whose placement is hard to explain: The laws of idolatry, the laws of sorcery, the laws of divination and the evil eye, and also the laws of niddah, which one would have expected to find in Even Ha'ezer, which deals with matters relating to women. Some say that whatever had no other place ended up there, and it requires study to know what his plan was.

Why se'if 10 appears here

It does not belong to Orach Chaim: This se'if deals with a prohibition on eating, not with berachos before or after food. Just as we do not say here that one may not eat meat without shechitah, but rather in Yoreh Deah, so too the prohibition of chadash does not belong here.
The main treatment is in Yoreh Deah: There it is discussed at length, in the laws of forbidden foods and in the laws of the mitzvos that apply to the land.
Why it is nevertheless brought here: Because the prohibition depends on the time of the omer and on the verse "from the day after the Shabbos," Rabbi Yaakov, the Baal HaTurim, inserted it here, and the Shulchan Aruch followed him. The entire se'if is therefore in the nature of an appendix. Still, since it is here, the Mishnah Berurah and the Biur Halachah expand on it, and it is a very practical subject.

The prohibition of chadash: the basis of the law

"And bread, roasted grain and fresh grain you shall not eat until that very day, until you have brought the offering of your God."
(Vayikra, Parashas Emor)

The scope of the prohibition: Until the omer offering is waved, one may not eat from the new grain, not as bread, not roasted and not fresh, and the prohibition applies to the five species of grain.
The time of the omer: The omer is harvested on the night of the sixteenth of Nissan, brought to the Beis Hamikdash on the morning of the sixteenth and waved there, and from that moment all of Israel may eat the new grain.
The omer permits it "in the borders": The Gemara's expression is that the omer permits the new grain "bagevulin," meaning for all of Israel everywhere, but not in the Beis Hamikdash.
The two loaves permit it in the Beis Hamikdash: Even after the waving of the omer, one may still not bring a minchah offering from the new grain in the Beis Hamikdash, and that prohibition lasts until the offering of the two loaves on Shavuos.
The difference between the two offerings: The omer offering comes from barley, which ripens earlier, while the two loaves come from wheat. That is why there are two offerings: the omer permits the eating of the people, and the two loaves permit the mizbeach.
The three categories of offerings: From animals, from birds (two turtledoves or two young pigeons) and from produce, and the omer offering and the two loaves belong to the category of produce.

The prohibition of chadash after the destruction of the Beis Hamikdash

The day itself permits: Once the Beis Hamikdash was destroyed there is no omer, and it was derived from the verses that when there is no omer, the day itself permits, that is, the date.
The difficulty: According to this, the new grain should have become permitted on the sixteenth of Nissan itself, at the very hour when the omer would have been waved.
The enactment of Rabban Yochanan ben Zakkai: Tomorrow the Beis Hamikdash may be rebuilt, and then eating will only be permitted after the waving of the omer. People who ate the previous year at an early hour will mistakenly think the matter depends on the day and not on the omer, and will eat before the waving. To avoid such a mishap he enacted that the whole of the sixteenth of Nissan is forbidden for eating chadash.
Anticipating the rebuilding: Here you see Rabban Yochanan ben Zakkai's anticipation, and likewise in several enactments in the Gemara the wording is "speedily the Beis Hamikdash will be rebuilt": a Jew has to think at every moment that tomorrow the Beis Hamikdash is being built.
The conclusion: The new grain is permitted only once the sixteenth has ended and the night of the seventeenth begins, and outside Eretz Yisrael a day is added, in the way that a second day is always added outside the Land.

"It is forbidden to eat chadash even nowadays, whether as bread, roasted grain or fresh grain, until the beginning of the night of the eighteenth of Nissan, and in Eretz Yisrael until the beginning of the night of the seventeenth."
(Shulchan Aruch)

(The extra day outside Eretz Yisrael has nothing to do with the growing seasons in various places; it stems from the very law of adding a day outside the Land.)

Defining "chadash": Mishnah Berurah s.k. 44

"It is forbidden to eat chadash: that is, grain that took root after the sixteenth of Nissan, which is the time of the cutting of the omer. But if it took root before the omer, the omer permits it, as is stated in Yoreh Deah, siman 293."
(Mishnah Berurah, s.k. 44)

The definition: Chadash is grain that took root after the sixteenth of Nissan; if it took root before then, that year's omer permits it.
Only in the five species: The prohibition applies only to the five species of grain.
The practical difference: Grain that was planted and took root after the sixteenth of Nissan is forbidden until the omer of the following year. In Eretz Yisrael this is not common, since there is no summer grain crop, but we are speaking of a particular variety or a case where grain was planted after that time.
How much rooting is needed: This is disputed among the poskim, and most opinions hold that three days before the sixteenth of Nissan is enough time for the grain to take root.
Where the details are found: The Mishnah Berurah refers us to Yoreh Deah siman 293, where the main discussion is; here the matter is treated only in passing. There it is also discussed how long rooting takes and whether there is a difference between barley, wheat and spelt.
The prohibition nowadays: The prohibition of chadash applies even nowadays, so one must know its laws, and it is a very practical matter.

In passing · questions left for further study

One who keeps Rabbeinu Tam's time for the end of Shabbos: The question was raised: for someone who is careful to end Shabbos according to Rabbeinu Tam, which comes first, sefiras ha'omer or havdalah? According to the rule stated here, that we push off the departure of the day as much as possible, it would seem that sefiras ha'omer comes first, but the matter was not decided here.
Which grain is actually forbidden: The question of grain imported from various places such as Ukraine, Russia or Argentina is a subject in its own right, and it does not bear on the question of how long the prohibition lasts. That matter will be discussed further on.