Quoting the “Divrei Chaim” blog:
Mountains of derush have been written on the fact that the aleph in VaYikra is small. The Zohar (quoted by R’ Tzuriel here ) writes that the letter is small because the revelation of Hashem here took place outside Eretz Yisrael and therefore lacked completeness.
Tzror haMor similarly writes:
למה אלף זעירא לפי שכבוד הש״י וקדושתו הוא בארץ ישראל לפי שהיא ארץ קדושה. וכשהוצרך לצאת מהיכלו ולילך חוצה לארץ כביכול הוא ממעט כבודו. ולכן נכתב ויקרא באלף זעירא.
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We are all “called” upon to work on our avodas Hashem. How many of us even realize how that calling from Hashem is diminished by virtue of our remaining in chu”l?
See the rest here…