May Jewish & gentile Catholics celebrate Seder Meals?

Robert Sungenis thinks not. If you visit his Catholic Apologetics International website, you will find not only his critique of the Jewish Catholic convert, Roy Schoeman, but at least five links to articles and discussions on whether Jewish traditions and customs under the Old Covenant (like the Seder Meal) have any abiding validity and worth for Catholics, and still more links on the question of the relationship between the two covenants.

The latest response to these statements is by Ben Douglass, a former associate of Sungenis, who takes issue with him in "A Last Response from Douglasstein" (Pugio Fidei, april 17, 2007). Among other things, he cites the following words of Pope Benedict XIV (fourteenth, not sixteenth) from his Ex Quo Prium (On the Euchologion):

If a man should perform acts for a different end and purpose (even with the intention of worship and as religious ceremonies), not in the spirit of that Law nor on the basis of it, but either from personal decision, from human custom, or on the instruction of the Church, he would not sin, nor could he be said to judaize. So when a man does something in the Church which resembles the ceremonies of the old Law, he must not always be said to judaize. [Ex Quo, 67]

He also takes issue with Sungenis' attempt (Q & A April 2007) to deflect the import of the following (related) words from Ex Quo Prium:

But others remarked wisely that some, surely, of the ceremonial rites of the old Law could be observed under the new Law if only they were not done as obligations of the old Law, which was abrogated, but as a custom, or lawful tradition, or as a new precept issued by one enjoying the recognized and competent authority to make laws and to enforce them, as Vasquez observes (vol. 3, in the 3rd part of the Summa, disp. 210, quest. 80, art. 7). [Ex Quo, 74]