The Sign Language of Tzaddikim
Tefillah
The Chofetz Chaim related that Rav Mordechai Bennet's talmidim once noticed that he had a habit of tracing the shapes of letters in the air with his finger. They watched closely and understood that he was tracing a verse from the tefillos of the Yamim Nora'im: Ashrei ish she'lo yishkachecha u'ven adam yis'ametz bach, happy is the man who does not forget You, and the person who strengthens himself in You.
He was reminding himself never to take his mind off his Creator.