The Torah is eternal. Its teachings apply to everyday practical life.
The beginning of our parashah speaks of war. "When you go to war against your enemies.” While in the simplest sense, the Torah is referring to the material enemies of the Jewish people, we can apply the same principles to our personal and current lives.
The enemy of Jewish - Jewish, it is the Yetzer Hara - the Inclination to evil.
Our sages tell us that the way to fight against our own inclination towards evil is through... Tefillah - the prayer.
When we pray, we generally put a lot of energy and effort into concentrating and truly feeling what we say. We may be struggling against our distracted mind, our heart that may be longing for other things, or our hands that may be fidgeting.
When we pray properly, thinking about HaShem and what He wants, we are overcoming our inclination to evil and winning the battle.
However, there is another way to win this fight, through the study of Torah.
He verse The verse says, "The ways of the Torah are pleasant, and its paths are peaceful." Instead of confronting the evil inclination by fighting it, we dedicate ourselves to the study of Torah.
When we engage in Torah study, our mood changes, and even our evil inclination is affected. Our study brings the holiness of HaShem into this world, changing everything for the better. The evil inclination also changes, becoming more eager to use its energies for good.
Extracted from Please tell me what the Rebbe says.