Second
(1) His words, “and this is our festival,” indicate that our festival is confined to this one; we have no other festival. The same sense is found in his words,

“and our festival is indeed this day,”

for the use of the definite article and the genitive construction together denotes totality, showing that the entire category of our festival is encompassed by the category of that day—just as in his saying
(2)

“its opening is the takbīr and its closing is the taslīm.” (3)

The Prophet—may Allah bless him and grant him peace—did not intend to limit the ruling to that specific festival or that exact day; rather, he was pointing to the general type that is divinely ordained. Thus the jurists say: “Chapter on the ‘Eid Prayer,” or, “The ‘Eid Prayer is such-and-such,” thereby including both ‘Eid prayers; likewise they say: “It is not permissible to fast on the day of ‘Eid.”

His words,

“and indeed this day,”

mean the class represented by this day—just as someone who observes a prayer might say, (4) “This is the prayer of the Muslims,” or, regarding the people’s going out (5) to the open field (6) and what they do there of takbīr, prayer, and the like, (7) “This is the festival of the Muslims,” and similar expressions. (8)