While perhaps not as famous as "Why is this night different from all other nights?" the phrase, "Let all who are hungry, come and eat," is certainly one of the more familiar quotations from the Haggadah.
And while there are varying interpretations of this concept, the notion of welcoming a stranger to the seder table is a central theme of Passover, according to several area rabbis.
"Inviting the stranger into the home is a core principle within Judaism," said Rabbi Pinchas Klein of the Congregations of Shaare Shamayim, a Traditional synagogue in the Northeast.
According to the Orthodox-trained rabbi, the roots of the idea can be found in the Torah, when Abraham and Sarah open their tent to literal strangers.
But Klein noted that, at least traditionally, the plea to invite a stranger to the table applied only to Jews. One explanation, he noted, is that in the days of the Temple in Jerusalem, only Jewish men could partake in the pascal-lamb sacrifice.
"Passover and the seder meal is the celebration of the inauguration of Jewish peoplehood," said Klein. Many contemporary seders take a far more universalist approach, and use the metaphor as the flight from Egypt for liberation from all kinds of social and historical injustices.
Today, said Klein, a debate exists within the Orthodox world over whether or not one should invite a non-Jew to the meal. Yet he doesn't have any problem doing it. In recent years, he's had a nun to his seder table, as well as several homeless people he met in North Miami Beach, where he lived until last year.
The more liberal streams have placed extra emphasis on the notion of inviting the non-Jew as a means for explaining the ritual to others and conducting interfaith relations.
"It is about enhancing interfaith understanding and shared dialogue, and helping our non-Jewish neighbors understand what their friends do," said Rabbi Kenneth Carr of Congregation Or Ami, a Reform synagogue in Lafayette Hill.
The most recent Haggadah published by the Reform movement's Central Conference of American Rabbis, The Open Door, plays heavily on the theme of the stranger, as well as the suggestion that the seder experience and the retelling of the Passover story are open to all.
"We don't want to perpetuate a sense of 'otherness,' " said the book's editor, Rabbi Sue Levi Elwell, director of the Pennsylvania Council of the Union for Reform Judaism. "This is an occasion where we can extend the table, that we can open the door. That doesn't mean we don't have very high standards for what happens at the table."
In a similar vein, Congregation Mishkan Shalom, a Reconstructionist congregation in the Roxborough section of Philadelphia, has established a tradition of its own for this purpose — the third seder. This year, on the festival's third night, the synagogue has invited members of the area's immigrant Muslim community to experience a nontraditional Passover meal.
"We were slaves in the land of Egypt, and we need to learn how not to enslave anyone else in any way," said Rabbi Linda Holtzman. The idea that non-Jews shouldn't take part in the Passover ritual "violates the heart of what the Passover experience was supposed to be about."
But Rabbi Yossi Kaplan of Chabad Lubavitch of Chester County insisted that the primary meaning of the phrase still applies to Jews. After all, many Jews are themselves strangers to the seder and the Passover experience, he Kaplan.
This year, because of the economic situation, Kaplan thinks that more people may actually be "spiritually hungry."