7891. And there shall be to you in the first day a holy convocation. That this signifies that in the beginning all shall be together, is evident from the signification of “the first day,” as being the beginning, namely, of liberation from those who have infested, and thus from damnation; and from the signification of “a holy convocation,” as being that all shall be together. Convocations took place in order that the whole assemblage of Israel might be together, and might thus represent heaven; for they were then all distinguished into tribes, and the tribes into families, and the families into houses. (That heaven along with the societies there was represented by the tribes, the families, and the houses of the sons of Israel, see n. 7836.) Therefore those convocations were called holy, and took place at every feast (Leviticus 23:27, 36; Numbers 28:26; 29:1, 7, 12). From this the feasts themselves were called “holy convocations,” for it was commanded that all the males should be present at them. That the feasts were called “holy convocations” is evident in Moses:
These are the set feasts of Jehovah, which ye shall call holy convocations, to offer a fire-offering unto Jehovah (Leviticus 23:37).
That at such times all males were to be present, in the same:
Three times in a year shall every male of thine appear together before Jehovah thy God, in the place which He shall choose; in the feast of unleavened things, and in the feast of weeks, and in the feast of tabernacles (Deuteronomy 16:16).
(References: Exodus 12:16)