What was the story of the Vilna Gaon scaring soldiers with his Tefilin?

Yes, there is a famous story about the Vilna Gaon and Russian soldiers that shows the power of true Yirat Shamayim and the holiness of tefillin when worn with complete kavana. The Gaon of Vilna was once learning in his Beit Midrash with his students when Russian soldiers suddenly broke in. These were dangerous men who would kill for fun. They came looking specifically for the Gaon, going from desk to desk, throwing tables and chairs, causing complete chaos. All the other students were terrified, falling to the floor, running away, scared to death. But the Gaon just sat there, continuing to learn Torah as if nothing was happening. He was wearing his tallit and tefillin, completely undisturbed, studying as though he was in Gan Eden. The soldiers got closer and closer to him, but he just kept learning. When they finally approached his table and were right in front of him, he looked up, took off his tallit that was covering his head, and revealed his tefillin. The moment those Russian soldiers saw his tefillin, they became absolutely terrified. The witnesses said the look on their faces was pure fear and trepidation, as if they were seeing Yom HaDin itself, as if a lion was about to tear them apart. They screamed and ran out of the building immediately. Now, all the other students were also wearing tefillin, but the soldiers didn't run from them. Why? Because when the students asked the Gaon what he did, he explained that it's written in the Torah in Devarim chapter 28 verse 10: "And all the nations saw the name of Hashem upon you and feared you." The Gemara in Masechet Berachot page 6b explains that this refers to the tefillin shel rosh. But the Gaon explained further: it's not just about wearing tefillin on your head, it's about having tefillin IN your head. The pasuk says "tefillin she'barosh" not "al harosh" because when you wear tefillin, you must think only about HaKadosh Baruch Hu every single second. Not about your mortgage, not about work, not about anything else. Only Hashem. When you do this with complete focus and purity, when the Shechinah is truly on you, everything that is the opposite of holiness becomes terrified and runs away. The other students were wearing tefillin, but their minds were wandering to other thoughts. The Gaon's mind was pure, focused entirely on Hashem. That's why the soldiers, who represented the forces of tumah, ran away from him in absolute terror but didn't run from the others. This teaches us that tefillin is not just a ritual. It's the crown of Am Yisrael, our connection to Avraham, Yitzchak, Yaakov, Moshe Rabbeinu, and Matan Torah itself. When we put on tefillin with true kavana and Yirat Shamayim, HaKadosh Baruch Hu protects us in ways we cannot even imagine.