The Jewish people received the Torah and reached a state where the sin of Adam HaRishon was rectified. If one didn’t merit to connect to this level of rectifying the sin of Adam HaRishon, is it possible for him also to connect to the event of standing at Har Sinai, which is the main avodah of this day [Shavuos], to connect to that event of Har Sinai? In our generation, how is it possible to connect to that event, when we are missing the necessary conditions which the Jewish people had at that time?
Through mesirus nefesh [willingness to give up our souls for G-d and for His Torah], we penetrate to the root of the spiritual level of the giving of the Torah. The root of the giving of the Torah was mesirus nefesh, because the souls of the Jewish people left them at every word of Hashem.