We hardly give a moment’s thought to the reason for wine at Seder Night. We’ve internalized the argument that the four expressions of redemption at the beginning of our parasha are memorialized through the four cups. The argument, however, is not particularly strong. The four varieties of redemption we experienced may call for four of something, but why wine? So many other items could have served the same function. We could eat four kinds of meat, or four vegetables, or even four different kinds of matzah.
Additionally, we must account for the mysterious fifth cup – the one over which the Gemara tells us to recite Hallel, yet whose presence at the Seder table is considered halachically optional. If this cup belongs to Hallel, why should it not be mandatory?
The Netziv answers both these questions in the process of offering a unique travelogue of the unfolding of our national redemption.
The purpose of the Exodus was to bring us to Sinai. But a nation of slaves, used to nothing more than toiling with bricks and mortar, cannot receive the Torah. Nor can it prepare itself in an instant to live by its expectations. The four expressions of redemption thus trace the path of the inner change we had to go through. Chazal underscored this change by using wine, itself an instrument of change in terms of our behavior, to mark the transformation of the Jewish state of mind.
In the first stage, Hashem took us out of the burdens of Egypt. In other words, He freed us from the harsh, servile labor of making bricks. This happened when the Egyptians were stricken by the fourth plague, arov. Yet, we remained technically slaves. While no longer forced to labor, we remained the legal property of others.
Barad changed the equation. For the first time, Pharaoh began to see us as people rather than chattel, begrudgingly giving us some respect even as he struggled to maintain his authority. This was the second stage, brought about by the second expression of redemption in which Hashem “saved them” from work. He saved us not only practically; even our definition was changed.
Our complete freedom was won with makas bechoros, which achieved the third stage in our reconstruction. We arrived at the finish line upon entering into the covenant with Hashem at Sinai.
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An aside: the Torah is not consistent in describing the first stage. It sometimes speaks of “a strong hand” while at other times mentioning “an outstretched arm.” Sometimes, it speaks of both. This is certainly not random.
The Gemara tells us that our dispersion to far-flung regions of the globe benefits us. Those who wish to harm us never have all of us within range. Pharaoh, however, did. Hashem’s show of His “strong hand” would not keep His people out of danger. Pharaoh could have responded to Hashem’s display of strength by destroying us quickly and efficiently.
To prevent that, Hashem reached out with “an outstretched arm” (which the Hagaddah interprets as a “sword”). He provided no respite for Pharaoh to strategize between makkos with a quick program of extermination. He did this through unrelenting pressure – an arm constantly poised to strike again and again, picking off Pharaoh’s associates and advisors and keeping him on the defensive. Pharaoh had no time to implement a plan to counterstrike against the Bnei Yisrael.
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Back to our original subject, the basis for a fifth cup of wine is, perhaps, a fifth expression: “You will know that I, Hashem, am your God.” This knowledge should not be confused with belief. It refers to understanding to the point that one’s knowledge allows him to become davek, attached to Hashem. This is not expected of everyone. True, Hashem promises that many of our people will utilize the Torah to launch themselves to new heights of understanding.
Not everyone shares this beracha, as they did the first four; and not everyone drinks the fifth cup, which belongs at the Seder as part of the story. It is a mitzvah to include it, but it is not obligatory upon all to mark it by drinking it.