שמות יט , א בַּחֹדֶש הַּשְלִישִ י לְצֵאת בְנֵי-יִשְר אֵל מֵאֶרֶץ מִצְר יִם בַּיוֹם הַּזֶה ב אוּ מִדְ בַּר סִינ י
The Gemara (Shabbos 89a) explains that the name of the mountain is סיני, since the giving of the Torah lead to the hatred from the people of the world (change the letter ס to the letter ש .) Why isn’t the mountain named הר אהבה (love) on account of the Jews receiving the precious gift of the Torah?
Perhaps this is comparable to the case of Esther. By pointing out the hatred that Haman held, Esther was able to increase the respect of the King towards Mordechai. Similarly, by pointing out the hatred of the nations of the world (who did not accept the Torah), this evokes a greater love from HaShem to the Jews that did receive the Torah. Thus, the name, that indicates love that comes out of the contrast to hatred, is greater than a name that would only indicate a direct love.
