Hashem revealed Himself to both Jews and Gentiles. Prophets also arose among the nations of the world upon whom the Spirit of God rested. However, the vast difference between the prophets of Israel and the prophets of the world is immediately apparent in the opening of the book of Leviticus. Moses, the greatest of the prophets of Israel, was granted a prophecy described by the words "And he called—Vayikra—to Moses." In contrast, Balaam—the greatest of the Gentile prophets—prophesied when God revealed Himself to him in a different way: "And God passed—vaykar—with Balaam.".
Rashi explains the difference: "All the commands were preceded by a call, an expression of love, a language with which angels deal, as it is written:3: and this one called to another. But to the prophets of the nations it was revealed with a circumstantial and impure language, as it is written: and God was passing by with Balaam.".
THE SYMBOL OF UNION
These two terms, 'vaikrá' and 'vaikar,' are very similar, and the only difference in their spelling is that 'vaikrá' has an additional letter, 'aleph.' This single letter brings about a profound change—from a terminology that implies circumstance and impurity to one of love, dedication, and holiness.
The letter 'Aleph' alludes to the "Alufó shel Olam," the ruler of the Universe—Hashem. Its numerical value is also one, thus representing the absolute unity of Divinity. It follows, then, that the term 'vaykra' reflects the bond between the Jew and God at a level of total union, where there are no two independent entities. In contrast, 'vaykar,' which lacks the 'aleph,' represents a casual bond, one that does not arise from a true union, a bond that implies impurity ('vaykar' is related to the text applied to Amalek, about which it is written: "who will 'korcha' you on the way").
EXPRESSIONS OF LOVE
This call from Hashem, in an expression of love, is directed not only to Moshe Rabbeinu, but to every Jew, since in every Jew resides a spark of Moshe Rabbeinu. The Most High reveals Himself to every Jew, in every generation, and specifically in a spirit of love and affection.
Furthermore, Rashi is not content with simply pointing out that the word 'vaikrá' is a language that expresses love, but adds: "a language with which angels communicate." Sometimes expressions of love can generate jealousy and competition. But among angels, there is no jealousy or competition, and this conveys the message that God's expressions of love toward each Jew are solely the cause of goodness, promoting unity and brotherhood, and not—God forbid—jealousy and competition.
ON THE WAYS OF HASHEM
This extraordinary love of the Almighty for every Jew should awaken in each member of the people of Israel a strengthening of love for other Jews and of Jewish unity. For if the Almighty Himself loves every Jew and reveals that affection to him, surely we should follow His path and love every Jew with a sincere and true love, reflecting true unity.
And in this way, in a spirit of total unity, the entire Jewish people march towards true and complete redemption, when we will see with our own eyes the materialization of the prophecy7: "And Hashem will be King over all the Earth, on that day Hashem will be One and His name One.".
(Sefer HaSichot 5749, Volume I, Page 336)
NOTES: 1.Vaikra 1:1 2.Bamidbar 23:4 3.Yeshayahu 6:3 4.See Sefer HaErjim Chabad Letter Aleph, article 16 5.Devarim 25:18 and Rashi's explanation there 6.Tania Ch.42 See Likutei Torah Vayikra 2,a 7.Zejaria 14:9