Some Catholics like to practice a Seder meal at some point prior to or during Holy Week. The Seder meal is only a pale shadow of the richness of the Catholic Mass. While it is understandable that the study of the Seder meal can bring a greater appreciation of the Mass, it is kind of silly.
First, how do you decide which traditional Jewish seder you want to look at? They aren't the same. For instance, the Ashkenazi have lamb at their Seders, the Sephardic and Mizrhaic Jews do not. Why the difference? Because the Ashkenazi say the lack of the Temple does not limit their ability to sacrifice the Passover lamb, while the other sects insist that no Passover lamb can be properly sacrificed anywhere but at the non-existent Temple.
Even if you decide on the tradition you want, what Seder ritual should you use? This is no small argument. I once had a discussion with a parish employee who insisted that the parish only use a Seder ritual which was acceptable to a(n Ashkenazi) rabbi. When I pointed out the absurdity of having a Jew tell a Catholic what kind of ritual could be carried out on parish property, she replied, "Well, how would you like it if someone did a parody of the Catholic Mass?"
I replied, "That happens every day. It's called Anglicanism."
The question of the Temple is important in another respect. Most parish Seder aficionados insist on having the Ashkenazi lamb at their Seder. Yet, even though they want the Seder and the lamb, the same people almost never also insist on ritually killing the lamb by slitting its throat in front of an observant audience. Why not? If you're going to do the Seder, why not do the whole thing?
Bring the kids in, especially the young ones! We like teaching them about the Eucharist by handing out Hawaiian bread and grape juice, why not help them gain an appreciation for Christ's sacrifice by slitting a lamb's throat and skinning it right in front of them as well? I promise they would never forget the lesson.
And if we're going to sacrifice lambs for the Seder, why stop there? Why not perform ritual animal holocausts on a regular basis at the parish church to commemorate the major Jewish feast days? So many Catholic feast days are built on the foundation of Jewish feasts that we should not overlook the opportunities the liturgical calendar affords.
Bring cows, sheep, lamb, doves! Wring doves' necks, slice throats, let the blood flow freely! Let them see what Temple Judaism really looked like! Then everyone will have a greater appreciation for the crucifixion.
Performing a Seder meal in order to appreciate the Mass is a lot like buying and playing with a Matchbox Hotwheels car so that you can better drive and appreciate a 2014 Toyota Camry. It just makes sense, right?
So, while you're sharpening your knives for the parish Seder, think on these things.