The first word of Sefer Vayikra seems to be misspelled. From afar, what should be read as Vayikra, spelled with a final aleph, appears more like vayikar (“he happened upon” conveying transitoriness), because of the diminutive aleph at the end. Why is there a miniature aleph? This question has impelled the commentators to suggest their homiletic insights. Chazal put it simply, distinguishing between the way Hashem spoke to the pagan prophets, such as Bilaam, and the manner in which He addressed Moshe Rabbeinu. Hashem’s prophecy to Bilaam is introduced with vayikar, related to the word mikreh, chance, and also is similar to keri, spiritual impurity, contamination – and neither connotation is very complimentary. Vayikar implies that Hashem’s relationship with Bilaam was one of necessity. If the need arose to convey a message, Hashem would speak with him. Moshe, on the other hand, had attained the apex of nevuah, prophetic spirituality. When Hashem addressed him, it was out of love; it was Vayikra, calling – a wholehearted, complete communication. Moshe, the anov (the most modest individual), did not want to call attention to himself. Therefore, he downplayed his unique relationship with Hashem, writing about himself Vayikra, but apparently spelling it vayikar with a diminutive and less noticeable aleph.
This would all be fine if this was the first instance that the Vayikra, He called, to Moshe, took place. We find in Parashas Yisro that Hashem called to Moshe from the mountain (Shemos 19:3), and on the day of the Revelation, Hashem called/summoned Moshe to the top of Har Sinai (Ibid. 19:20). Those scenarios presented opportunities for Moshe to manifest his consummate humility. Why then is the “calling” in Vayikra the first and only time that Moshe demonstrated his humbleness?
Horav Yitzchak, zl, m’Vorka explains that humility is expressed in private. Public humility is subtle arrogance! When one makes a point of acting with extreme modesty when he is in the public view, he is not being modest at all. Moshe Rabbeinu’s reduction of the aleph, was a covert act. Hashem’s summons was between Moshe and the Almighty, unlike the Revelation which took place in the presence of the entire Jewish nation. Moshe thought he could “get away” with diminishing the “size” of his encounter with Hashem. Like all of those who are truly humble, he did not succeed in his self-effacement.