Rabbi Lawrence Hajioff - Rashi's Siddur
The clearest explanation of the question as to how we are expected to feel as though we personally left Egypt is given in the Siddur of Rashi, written by one of Rashi’s students. He explains that the Haggadah is attempting to invoke a feeling of gratitude on our part. Our ancestors were actually in Egypt. Through an incredible display of miracles that G-d displayed in Egypt, our ancestors were taken out. Had they not been released from Egypt, they would have totally assimilated into Egypt and we would never have left at all. Our history came down to that one crucial moment, do we stay or do we go?
According to the commentators many Jews decided that they actually did not wish to leave and after over 200 years, they felt more Egyptian than Hebrew. Many of them died out in the plague of darkness, but many others remained and became part of Egyptian society and culture. Their descendants are not considered Jewish. They never made it to Mount Sinai which would have sealed their destiny as part of the Jewish people. However, hundreds of thousands did leave with a faith in G-d and Moses his messenger.
By recalling that fateful decision our ancestors made all of those years ago, we can sit at our tables and say, “had they not been taken out, we would still be there, so it’s as though were taken out ourselves.”
Sephardic Custom A
Much of the seder is meant to symbolize the Jews’ enslavement in Egypt (think: the salt water during Karpas represent tears, and the charoset symbolizes the mortar used in the Jews’ slave labor.) However, in some places of the Middle East, Jewish families take this one step further by literally hitting each other with scallions (green onions) while singing the dayenu song. This custom is indigenous to countries like Persia and Afghanistan and is meant to signify the whips used by the Egyptians on their Jewish captives. Don’t worry, though, if you choose to take on this custom, you’ll only be hit lightly with the onion frond.
Sephardic Custom B
While the basic text of the Haggadah and format of the seder is the same around the world, each community has its own unique customs. One such custom that is pervasive throughout the Sephardi communities is to dramatize the Exodus. Generally this takes place immediately following Yachatz, the breaking of the middle matzah, or after Ha Lachma Anya, the first paragraph of the Maggid section.
The basic script for this dramatization is as follows:
Person holding the afikomen (larger half of the broken matzah) says: "Their remaining possessions tied up in their bags on their shoulders and the children of Israel did as Moses commanded.”
Other Seder Participants: “From where are you coming?”
Afikomen holder: “From Egypt.”
Participants: “Where are you going?”
Afikomen holder: “To Jerusalem.”
Participants: “What are your supplies?”
Afikomen holder: “Matzah and Maror.”
This ceremony varies not only as to when it is said, but also who says it (sometimes only the leader, sometimes one child gets up and knocks on the door before the dialogue begins, and sometimes each participant of the Seder holds the afikomen in turn), and how the afikomen is wrapped and held (in a napkin or a bag, held on the right shoulder or thrown over the shoulder).
In the Yemenite community, there is a slightly different re-enacting of the Exodus. The seder leader rises, throws the afikomen bag over his shoulder like a knapsack and circles the table while leaning on a cane. As he walks about the room, the leader tells the other participants about his experiences and the miracles he witnessed as he came from Egypt.
Rabbi Lawrence Hajioff - Summary of Rav Shimon Schwab
One of the most intriguing answers in how we are expected to see ourselves as though we left Egypt comes from Rav Shimon Schwab in his book Maayan Beit Hashoeiva, Shemot 13:8.
His mind-bending interpretation is that you were there, you just don’t remember being there. When the Torah says “What Hashem did for me” that is a literal verse -- it is not speaking in metaphorical or theoretical language; the Torah says it because the Torah means it. You were in Egypt, and you were taken out.
He explains this phenomenon in the following way: Your body is made up of many parts. It is a known fact that the body you have now is not the same body you had as a baby or even as a child. Over your many years living on earth your body has changed. You not only have grown, but billions of your cells have died out and new ones have appeared. If you were to look at a picture of yourself as a newborn, you most likely wouldn’t have realized it was you without your mother telling you that you are the cute baby in the photo. That baby doesn’t look like you, sound like you, smell like you or feel like you, but it is still you. You don’t even remember being a newborn! But that was you whether you remember it or not.
The Jewish people are very much the same. Our ancestors are not different people who we descend from, they are us, just an earlier version of us, just like that baby was us all those years ago. The fact that those Jews in Egypt sounded, looked and acted differently is irrelevant. You are looking at the Jewish people the wrong way, says Rabbi Schwab — we are one large organic being that spans thousands of years of Jewish history. We were “born” as a people in Egypt over 3,000 years ago and have slowly been growing as a people ever since then.
From the David Moss Hagadah