D'var Torah: "This is the decree of the Torah" (BaMidbar 19:2). Torah is the revelation of Divine wisdom, that lights the way for us in this world and grants us eternal life in the World to Come. Even more, Torah study fills our hearts and souls with the joy of spiritual sweetness. The holiness and purity of the Torah permeates our being, so that no impurity can influence us. This explanation sheds light on the verse, "This is the decree of the Torah." Meaning, the Torah decrees that as long as a person is alive, the sanctity of Torah protects him from impurity.
Moral: The sweetness of the Torah continuously imparts powerful healing measures of holiness, joy, and spiritual protection within our hearts, which counterbalances all negativity.
Application: Envision Moshe Rabenu engaging in Torah study. See the light of holiness shine on his countenance. Sense his deep joy, true wisdom, and inner peace. Reflect on the great healing power and protection that Torah study gives to you. Fill your soul with the holiness of Torah, inner joy, and tranquility.
(Based on the commentary of the Ohr HaChaim)