The most famous answer to this question revolves around two verses in
"Therefore, say to the children of Israel 'I am
Hashem, and I SHALL TAKE YOU OUT from under the burdens of Egypt; I SHALL
RESCUE YOU from their service; I SHALL REDEEM YOU with an outstretched arm
and with great judgments. I SHALL TAKE YOU TO ME for a people and I shall be
a G-d to you...."
In these two verses, we find what are termed "The Four
Expressions of Redemption." G-d said to the nation of Israel using four
different expressions that they would be taken out of slavery in Egypt. We
therefore drink a cup of wine, on this night that we commemorate our
redemption, for each expression of redemption that G-d uttered.
The Sh"lah gives another reason. On this night, we celebrate the birth of the
Jewish people as a nation. We read in the Hagadah about our forefathers.
Avraham originally worshipped idols. His son Yitzchak had two children,
Yaakov and Esav. Yaakov ended up in Egypt where his son Yosef was. However,
we do not read of the contributions of our mothers to the development of the
nation of Israel. Each cup of wine represents one of our matriarchs. The
first cup of wine is used to recite Kiddush, the sanctification of the day.
In the Kiddush, we read how G-d has sanctified the nation of Israel with His
mitzvos (commandments), which makes the Jewish people unique. Sarah was known
for her efforts to spread the word of G-d to those who previously worshipped
idols. It is with Kiddush, where we speak of this sanctification of the
nation of Israel, that we commemorate Sarah, who exerted efforts to bring
others into this fold.
We drink the second cup of wine after we have told the story of the birth of
our nation. We have read how Avraham originally worshipped idols. We have
read how the nation grew and developed. Rivka's life progressed in a similar
fashion. She was born into a family of idol worshipers and she grew to be one
of the matriarchs of the nation of Israel. With the second cup of wine, we
commemorate Rivka, who overcame an idolatrous background to become the
mother of the Jewish people.
After we conclude the Grace After Meals, we drink the third cup. Rachel was
the mother of Yosef, who assured that the entire land of Egypt would have
sustenance during the years of famine. It is fitting that we remember Rachel,
the mother of the one who sustained a nation, after we have completed our
The last cup of wine is drunk after we complete Hallel, the praises of G-d.
Leah, upon the birth of her son Yehudah, said "This time I shall thank
Hashem." Why did Leah thank G-d upon the birth of her fourth son, and not
with the previous three? The answer is that Leah realized that Yaakov was to
have 12 children between his four wives. When she had her fourth son, she
realized that she was given one more than her "share" in the unit that was
the base for the nation of Israel. Of course she was thankful with each
child. But with Yehudah, Leah knew that she had received something truly
special, above and beyond what she should get. Therefore, she thanked Hashem
when Yehudah was born. It is fitting that after we finish thanking Hashem for
taking us out of Egypt, we remember Leah, who taught the Jewish people how
and when to say thank you.
Check out all of the posts on Pesach and the Hagadah! Head over to
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Page, and click on the holiday you are interested in to find all of the
archived posts on that topic.