Arelus In Kodshim

The Torah says regarding the Korban Pesach כל ערל לא יאכל בו.  The Mishna in Yevamot 70a teaches that an ערל  is prohibited from eating terumah as well.  The Gemorah brings a machlokes as to what the source of the din is.  The Gemorah on 72a and 74a is clear that there is a prohibition on an ערל to eat other kodshim as well.  However, it is unclear from the Gemorah what the source of the issur is.  The Minchas Chinuch 17:7 assumes that the issur is derived from the Pesach.  The Briskor Rav brings many proofs from the Rambam that its derived from terumah.  See Rambam Sefer Hamitzvot #135, perush hamishna beginning of Ch. 7 Yevamot (see Briskor Rav in Maacolos Assurot.)

The Gemorah in Pesachim 28b says that בו הוא דאינו אוכל, but he eats matzah and maror.  The simple interpretation is not permission to eat matzah and maror, but that he must eat (see Tosfos there.)  However, the Rambam Laws of Korban Pesach 9:8 seems to understand the Gemorah is telling us a heter that one may give matzah and maror to a ger toshav.  If the issur of an ערל to eat kodshim is a general issur derived from the pesach why would you assume the issur extends to pesach and maror?  We see that the issur ערל to Pesach is distinct from that of kodshim and we would have extended it to the other mitzvot of the night of Pesach (Briskor Rav Temurah 2ab)