Comentario citado sobre Isaías 1:13

מועדי ה' אשר תקראו אותם מקראי קודש, after the Torah had spoken on the subject of the animal offerings and the people offering them whose purpose it is to ensure that the Shechinah rests in/over the people of Israel. Compare Exodus 29,42 עולת תמיד לדורותיכם, פתח אהל מועד לפני ה' אשר אועד לכם שמה; “a regular burnt offering throughout the generations, at the entrance of the Tent of Meeting before the Lord.” The Torah spoke of the festivals, days on which one abstains from the pursuit of secular matters. On some of these days one has to abstain from such activities completely, on others only partially. For instance, on the Sabbath as well as on the Day of Atonement there is a total cessation of everything which is called מלאכה, work, in the sense of a productive activity. These days are meant for us to occupy ourselves exclusively with Torah and other sacred tasks. To this effect the Torah wrote (Exodus 20,9-10) “you shall labour for six days and conduct all your activities, whereas the seventh day is a Sabbath of the Lord your G’d.” On that day your activities should concern spiritual matters. On some of the days described as holy convocations there is a partial prohibition of work, desisting basically from the kind of activity related to the kind of labour involved in earning one’s livelihood. One is to enjoy these days. Concerning such days, our sages coined the phrase חציה לה' וחציה לכם, “half for G’d and half for you.” (Pessachim 68) There is no doubt that when the Jewish people conduct themselves in this fashion that the Divine Presence will be at home among them. Assaph expressed this thought in Psalms 82,1 which commences with the words אלוקים נצב בעדת א-ל וגו', “G’d stands in the divine assembly. Among the divine beings He pronounces judgment.” The meaning of the word מקראי קודש when applied to the days the Torah calls מועדי ה' אשר תקראו אותם מקראי קודש is: “days of assembles of the people for sacred undertakings.” The word מקרא refers to an assembly, just as the words שבת and חודש are understood as meaning assemblies both in Isaiah 1,13 and Isaiah 4,5

Why do Chazal condemn Daniel for advising Nevuchadnetzar to give Tzedaka?
An answer emerges from Yeshayahu who famously condemns the bringing of Korbanot: “Lamah Li Rov Zichveichem” (Yeshayahu 1:13 – which we read on Shabbat Chazon). Why does Yishayahu condemn us for fulfilling a Mitzva set forth in the Torah? We believe that it is because offering Korbanot for the wrong reason misses the point and is even harmful to the Neshama.

חדש בחדשו a new moon on the day appointed for it. Comp. דבר יום ביומו the task of every day on the day appointed for it (Ex. 5:13). From this verse the ancients derived that the wicked had to suffer the future punishment for twelve months;^42aSee Midrash Yalkut ad locum. they explain the word מדי to signify one year.⁴³This seems to be I. E.’s interpretation of the passage quoted from the Midrash; but this explanation of מרי is not found there. The meaning of מדי שבת בשבתו I have explained in my commentary on the chapter concerning the seven weeks.^43aLev. 23:9-22, or ib. 25:1-13. The words מדי שבת בשבתו are explained in neither of the two passages. I. E. is perhaps of opinion that the expression שבת, used here by the prophet, includes also the festivals, and he refers therefore to his remark on Lev. 23:11, in which he proves that the word שבת in the phrase ממחרת השבת refers to the first day of Passover.