These Halachos (except for passages found in [* ]) are copied from Rabbi Blumenkrantz's book

"The Laws of Pesach"

Some Important Information for the Seder

Chapter Nine

Shiurim - Measurements

D. Do It Right On Pesach Night - Shiurim - Measurements

What? When? How Much?

Required amounts of ritual foods and beverages for the Pesach Seder were compiled by Kollel Beth Medrash L'Torah VHoroah, founded by Hagaon Harav Moshe Feinstein Zt"1, and presently under the leadership and guidance of his son, Hagaon Harav Dovid Feinstein, Shlita.

NOTE: These minimum requirements must be adhered to by women as well as men.

1. Four Cups Of Wine

On a regular Friday, night, or when the Seder falls out on Friday night, because Kiddush is a Biblical requirement (Medeoraiso), the Kiddush cup should hold at least 4.42 fl. oz. However, since the Kiddush on a regular Yom Tov, including Pesach, is a Rabbinical (Miderabonon) requirement, the Kiddush cup can hold as little as 2.9 fl. oz.
After Go’al Yisroel - the cup should hold 2.9 fl. oz.
After Bircas Hamzon - the cup should hold 2.9 fl. oz.
After Hallel - the cup should hold 2.9 fl. oz.

It is suggested that the cup be able to hold more than the 2.9 ounces required, to compensate for some spillage.

The wine should be consumed preferably in two swallows. There are some authorities who hold that the wine can be drunk in a span of two minutes, while other authorities allow up to nine minutes.

2. Matzo
For Hamotzi and for Afikomen a piece measuring 7 x 6-½ inches is required.
For Korech -a piece measuring at least 7 x 4 inches is required.

Why Three? The men of Kairwan asked their great Rabbi and leader, Rav Sherira Gaon, "Why do we take three matzos on the night of Pesach --no more and no less?" He answered: "There is an allusion to this number in the Torah, namely, the three seah measures of fine flour that Avrohom told Sarah to knead and prepare 'round cakes' for his guests (the angels who where visiting him) which took place on Pesach. Others say that the number commemorates the "three mountains of the world", Avrohom, Yitzchok and Yaakov.

If for health reasons, one can't cat matzo, then Shmura matzo meal (upon which Hamotzi will be recited) may be substituted as follows:

a. For Hamotzi and Afikomen an amount of meal that can be compacted into a 1.5 fl. oz. vessel.
b. For Korech an amount of meal that can be compacted into a 1.1 fl. oz. vessel.
3. Morror
a. If you use pure grated horseradish:
1. For Morror 1.1 fl. oz
2. For Korech 7 fl. oz.
b. If you use Romaine Lettuce leaves:
1. For morror - Enough leaves to cover an area of 8 x 10 inches.
2. For Korech -The same.
c. If you use Romaine Lettuce stalks:
1. For Morror -Enough to cover an area of 3 x 5 inches.
2. For Korech -The same.
The required amount of matzo and morror should, in each case, be eaten in a span of two minutes according to some, or up to nine minutes according to others.

Before the beginning of the holiday, it is advisable to measure a jigger to find out its fluid ounce measurement. Then, at the Seder, one can pack the jigger with enough of the matzo meal and grated horseradish needed to meet the required amounts.

Below, you will find the explanation of how the above measurements were derived. Before we begin the computations, we will cite four laws mentioned in. the Shulchan Aruch:

A. The size of a cup for the four cups of wine at the Seder is a Reve'es.
B. A Reve'es is the amount of water displaced by a middle or average sized egg and a half (1½eggs).
C. The amount of matzo and morror needed to perform the mitzvos of matzo and morror is a Kzais.
D. Some say a Kazais is equal to half (½) an average egg, whereas others say it is equal to a third (1/3) of an average egg.
Now, let us do the computations. We have three different methods of measuring a Reve’es:
1) through the water displacement of eggs (by experimentation);
2) through thumbs, and;
3) through stricter thumbs.
1. Through Eggs

The water displacement experiment was done with what is commercially known as a large egg. This egg was assumed to be the "average" egg referred to by our Sages for two reasons;

a) The large egg is the "middle" sized egg in the five (5) sizes of eggs commercially sold (small, medium, large, extra-large, jumbo).
b) The large egg is the average consumed egg in the world. After this decision was made, we realized that large eggs are not all the same; there is a minimum and maximum weight requirement that eggs must satisfy to be categorized as large.
The average weight of a large egg displaces 1.93 fl. oz. of water, while the maximum weight of a large egg displaces 2.2 fl. oz. Therefore, an egg and a half (which is a Reve'es) is equal to 2.9 fl. oz. and 3.3 fl. oz., respectively.
2. Through Thumbs:
In Psochim 109, the Sages teach us that a Reve'es fills up a cup of two thumbs by two thumbs by 2.7 thumbs (2 x 2 x 2.7 thumbs).
1 thumb 1/24 of an Amoh
1 Amoh 21.25 inches (according to Igros Moshe 136)
In order to be "sure" we must add half a thumb on the Amoh, which is equal to .4427 inches.
A "sure" Amoh = 21.6927 inches.
Accordingly; 1 "sure" thumb = .90386 inches;
2 "sure" thumbs = 1.80772 inches;
2.7 "sure" thumbs = 2.44042 inches. Therefore;
2 x 2 x 2.27 cubic thumbs = 7.97484 cubic inches = Reve'es.
Now to find how many fluid ounces we get in a cup of 7.97484 cubic inches, we must work with gallons. We know that;
1 gallon 231 cubic inches, and holds 128 fluid ounces. By dividing 128 into 231, we deduce that:
1 fl. oz. 1.804 cu. in. Therefore by dividing 7.974984 by 1.804, we find that 7.974984 cu. in. holds 4.42 fl. oz.
3. Through "Stricter" Thumbs: A "Strict" Amoh = 23 inches (Igros Moshe 136).
(On this Amoh, we do not have to add half a thumb as we did above, because this measurement by itself is a strict measurement.)
1 thumb = 1/24 Amoh = 1/24 (23) =.95834 inches.
2 thumbs =1.91668 inches
2.7 thumbs = 2.56752 inches. Therefore a cup of 2 x 2 x 2.7 thumbs = 9.50569 cubic inches.
Going through the same computations as in (2) above, we find that 9.50569 cu. in. holds 5.27 fl. oz. We conclude that a Reve'es = 5.27 fl. oz.
Based upon the above information we can now compute the measurement of a K'zais. Remember, the sages disagree concerning the definition of a K'zais. Some say it is equal to 1 2 an average egg, and others say it is equal to 1/3 of an average egg.
Reve'es = (a) 2.9 fl. oz., (b) 3.3 fl. oz., (c) 4.42 fl. oz., (d) 5.27 fl. oz.
Reve'es = 1½ eggs
If a Kazais = ½ egg =
(a) .97 fl. oz., (b) 1.1 fl. oz., (c) 1.47 fl. oz., (d) 1.75 fl. oz.
If a Kazais = 1/3 egg =
(a) .65 fl. oz., (b) .7 fl. oz., (c) .98 fl. oz., (d) 1.16 fl. oz.

Now that we have shown the computations, let us show how to apply them.

a) Because Kiddush Friday night is D'oraiso, we should use the middle Reve'es (4.42 fl. oz.). Since the other Kiddushim, and the Four Cups of Pesach are M'derabonon, it is enough to use the Reve'es of 2.9 fl. oz.

b) Since the Kazais of matzo is D'oraiso, we should use the Kazais of 1.47 fl. oz.
The chumro of two zeisim of matzo mentioned in Oruch Chaim (Ch. 475) can be fulfilled by eating the 1.47 fl. oz. Kazais because this quantity is equal to 2 zeisim of .7 fl. oz., or 1.4 fl. oz.

Let us explain how to find how many fluid ounces are contained in each matzo. A pound (1 lb.) of matzo meal will fill a cup which holds approximately 31 fluid ounces.
Therefore, determine the number of matzos per pound, and divide into 31 fluid ounces. This will indicate how many fluid ounces are contained in a matzo. One will then know how much of a matzo must be eaten for a K'zais.

c) For the matzo of Korech, which is M'derabonon, a Kazais of 1.1 fl. oz. is permissible or, when necessary, even one equalling .7 fl. oz. is permitted.

d) Matzo for afikomen -The same as for matzo (see (b) above).

e) For moror, a Kazais equal to 1.1 fl. oz. is used.

f) Morror for Korech, a Kazais equal to .7 fl. oz. is used.

By understanding the above computations, you may have a clearer understanding of the halachic discussion of whether our eggs have become smaller, or our thumbs larger than the average egg and thumb which existed in the days of our sages.


A. The cup of the Chofetz Chaim held 5 fluid ounces, while the cup of Rabbi Yisroel Salanter held 4.1 fluid ounces. The Chazon Ish Zt"l held that the cup should not hold less than 5.07 fl. oz. while the Chofetz Chaim held that the cup should not hold less than 4 fl. oz.

The cup of the Rebbe of Satmar, Zt"1, for Kiddush was 4.75 fl. oz., while for Havdoloh, he used a cup of 2.5 fl. oz.

B. We mentioned above that the Talmud teaches us that 1 Kazais = ½ betzah, and 1 Reve'es = 1½ betzah.

The Rambam reckons this Talmudic betzah as the volume of 18 'drams' of water, the dram having been a standard measure in his time, and this value is quoted and used in practice by the Shulchan Aruch, and later authorities down to the present day, including the Bed Ish Chai. The 'dram' referred to is equivalent to slightly more than three metric grams and hence, since the volume of a gram of water is exactly one cubic centimeter, it follows that

and these are the traditional measurements.

However, some of the later authorities (Noda B’Yehuda, Chazon Ish) performed their own experiments using the original Talmudic guidelines and felt forced to the conclusion that the betzah referred to must be double the size of an average modern egg. The implication of their results is that during the eight hundred-odd years since the Rambam, the 'dram' did not remain a standard measure but became smaller; hence the apparent discrepancy between his measurements and those of the Talmud. According to this theory,

These are known colloquially as "the Chazon Ish measurements" after the great Torah giant of the first half of this century, Zt”l, who was a leading exponent of the theory.

Although these new measurements are not the generally accepted custom and, indeed, there are authorities who challenge the validity of the proof altogether (Chasam Sofer, Rav Chayim Noeh), the great Rabbi Yisroel Meir HaCohen zt”l, author of the Mishnah Brurah has suggested that where it is a question of fulfilling, or not fulfilling, an original Torah command (as opposed to a Rabbinical one) - in an absolute sense - it is worth taking account of these new measurements, if possible.

Chad Gadya
CHAD GADYAH is the conclusion of our Seder Night Celebration.

We do not know the name of its author and nor much about the time of its introduction into the Hagadah. It was probably composed in the 15th century. Our commentators saw in it references to various events and characters. The obvious point in it is the idea of Hillel's saying in the Pirkei Avos: . "Al de-atteift, atfuch." Because you drowned someone, you were drowned.

According to some explanations the father who bought the kid is G-d who called upon the Jewish people to become his nation who are compared to a kid.

The two Zuz are either Moses and Aaron or the two tablets. The cat is Ashur (Nebuchadnezzar) who killed many Jews. It was bitten by the dog (Babel) which in its turn was smitten again by the stick (Persia). Then came the Greeks (fire) and conquered the Persian Empire. They again were beaten by the Romans (water). The ox symbolizes the Saracenes who afterwards turned out the Romans and took possession of Palestine, Their fate was sealed by the crusaders (the slaughterer) until the Angel of Death came and took it out of their hands. In the end the Almighty will redeem His people from all its enemies.

Shir HaShirim
Some people have the custom to read Shir HaShirim out loud, slowly, and with a melody at the end of the Seder. They do this for two reasons: 1) The Song of Songs is an allegory describing the love between G-d and the Children of Israel which began with the Exodus. 2) The Song of Songs also makes explicit reference to our exile in Egypt, and our redemption, culminating with the miraculous parting of the Red Sea, with the passage ..."to a steed in Pharaoh's chariots." (Song of Songs 1:9)

At this point it is time for everyone to learn the Halochos of Pesach and to talk and discuss the Exodus and other miracles that the A-mighty did for our fathers, until sleep overcomes him.

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