Each cup of wine is derived from the language of redemption.

God said to Moses, in the book of Shemot, Exodus, in Chapter 6 -

לָכֵ֞ן אֱמֹ֥ר לִבְנֵֽי־יִשְׂרָאֵל֘ אֲנִ֣י יְקֹוָק֒ וְהוֹצֵאתִ֣י אֶתְכֶ֗ם מִתַּ֙חַת֙ סִבְלֹ֣ת מִצְרַ֔יִם וְהִצַּלְתִּ֥י אֶתְכֶ֖ם מֵעֲבֹדָתָ֑ם וְגָאַלְתִּ֤י אֶתְכֶם֙ בִּזְר֣וֹעַ נְטוּיָ֔ה וּבִשְׁפָטִ֖ים גְּדֹלִֽים:

וְלָקַחְתִּ֨י אֶתְכֶ֥ם לִי֙ לְעָ֔ם וְהָיִ֥יתִי לָכֶ֖ם לֵֽאלֹהִ֑ים וִֽידַעְתֶּ֗ם כִּ֣י אֲנִ֤י יְקֹוָק֙ אֱלֹ֣הֵיכֶ֔ם הַמּוֹצִ֣יא אֶתְכֶ֔ם מִתַּ֖חַת סִבְל֥וֹת מִצְרָֽיִם:

 וְהֵבֵאתִ֤י אֶתְכֶם֙ אֶל־הָאָ֔רֶץ אֲשֶׁ֤ר נָשָׂ֙אתִי֙ אֶת־יָדִ֔י לָתֵ֣ת אֹתָ֔הּ לְאַבְרָהָ֥ם לְיִצְחָ֖ק וּֽלְיַעֲקֹ֑ב וְנָתַתִּ֨י אֹתָ֥הּ לָכֶ֛ם מוֹרָשָׁ֖ה אֲנִ֥י יְקֹוָֽק: 

Say, therefore, to the Israelite people: I am the LORD. I will free you from the labors of the Egyptians and deliver you from their bondage. I will redeem you with an outstretched arm and through extraordinary chastisements.

And I will take you to be My people, and I will be your God. And you shall know that I, the LORD, am your God who freed you from the labors of the Egyptians.

I will bring you into the land which I swore to give to Abraham, Isaac, and Jacob, and I will give it to you for a possession, I the LORD.”

והוצאתי - I will free you

והצלתי - I will save you

ןגאלתי - I will redeem you

ולקחתי - I will take you [as a nation]

והבאתי - I will bring you [to Israel]

The fifth cup was an old custom, mentioned in the Talmud. They were of the opinion that the cup was not obligatory, but a nice addition to acknowledge that our redemption doesn't end with our nationhood, rather with our presence in Israel. Over the years the Zionists have popularized the custom as a statement of the importance of the state of Israel.


haggadah Section: Hallel
Source: Zev and Eden