Шмот 26:2 Комментарий: Chizkuni, Rabbeinu Bahya & Rav Hirsch

אורך היריעה האחת, “the length of each strip of cloth, etc.;” the letter א at the beginning of the word ,האחת, has the vowel patach, whereas the second time it has the vowel segol, and the third time it occurs it again has the vowel segol. When the Torah speaks of the goats’ skins, we find the same pattern. The rule is that when the letter א in the word אחת had the vowel patach, and is followed by a word with the separating cantillation mark etnachta, the next time the word אחת occurs it has the vowel segol if the cantillation marks are either zakef katan, or sof passuk.

אורך היריעה האחת שמונה ועשרים באמה, “the length of a single curtain was approximately 28 cubits.” It is common knowledge that the entire Tabernacle and its components were meant to be sort of a replica of what exists in the heavens (primarily the parts we can see). Seeing that the luminaries are fixed in the sky, and all their activities inasmuch as they have impact on our terrestrial world are decreed to occur at predetermined times, the Torah called the Tabernacle, i.e. the covering, the ceiling of the structure, by the name יריעה, “curtain.” David uses the same expression to describe the heaven in psalm 104,2 where he speaks about G’d as נוטה שמים כיריעה, “spreading the heaven like a tent (curtain).”
There were a total of ten such curtains corresponding to ten different גלגלים, i.e. the seven fixed stars, plus what is known as the גלגל השכל, גלגל המקיף, and the גלגל המזלות, the domain (orbit) of ‘intelligence,’ a domain which surrounds all the planetary systems, near the domain of the sign of the zodiac. The reason that the length of each curtain was to be 28 cubits was that it was to correspond to the 28 times Solomon mentions the word עת in Kohelet chapter three. With regard to the significance of that word עת, we read in Chronicles I 12,32 that the men whom the tribe of Issachar dispatched to participate in the crowning of King David were all יודעי בינה לעתים, “conversant with the meaning of these different periods described as עת.” David himself said concerning the significance of each different time period: אברכה את ה' בכל עת, “let me bless the Lord in each one of these time periods” (Psalms 34,2). Another occasion when David mentions the word עת specifically is in Psalm 31,16 בידך עתתי, “my times are in Your hands.”
Another reason for the number 28 may be connected to the lunar cycle, i.e. the number of days the moon either gains or loses size (according to our observation).

Midrash Tanchuma (Terumah 9) in referring to the length of 28 cubits of each of these curtains claims that there was a basic miracle involved here as we never find curtains of this length (about 56 feet). According to Rabbi Nechemyah this was a miracle that occurred only in connection with the weaving of these special יריעות. Actually, miraculous occurrences took place not only in connection with these curtains but also in connection with the קרשים, the upright beams forming the walls of the Tabernacle.