So if you are being disturbed when praying or studying Torah, by a person or any other way, take it as being for your good -- that you were not concentrating properly, and so heaven sent you this disturbance to make you aware that you should strengthen your kavvanah. (Keter Shem Tov)

The Baal Shem Tov in Jewish Spiritual Practices by Yitzhak Buxbaum