In this week's Parsha, just before מתן תורה, the Pasuk says ויחן שם ישראל נגד ההר, "Bnei Yisrael camped next to the mountain." Rashi has a famous comment on the words ויחן שם ישראל, that the Torah describes the encampment in the singular form, (ויחן) because the people were unified - בלב אחד. The lesson for us is obvious - in order to perpetuate the Sinai experience, (see Rashi on י"ט:א), we must be unified. We must not fight with each other or speak disparagingly about one another, even if one is not observant of Torah law. The Gemara (יבמות סב:) relates that 42,000 of Rabbi Akiva's students died. The Gemara says that they did not die because they were not תלמדי חכמים, but rather because שלא נהגו כבוד זה לזה, that they did not act respectfully towards one another. This teaches that in order for Torah study to be widespread, people must act kindly and respectfully to others. Rashi (שמות ב:יד) explains that when Moshe discovered that Jews spoke evil about each other, he understood why Hashem punished them with the terrible burden of slavery. Indeed, the חפץ חיים emphasizes that one who habitually speaks Lashon Hara will have all his meritorious deeds performed in this world cancelled. The only way more Jews are to become observant is if Torah observant Jews speak and act kindly towards each other. When we finally stop speaking Lashon Hara, we will once again experience the unity of Sinai.