Gentleness toward thieves
The defining feature of Gregory's life in the tradition is his treatment of those who came to rob him. The synaxarion relates that robbers broke in on him several times, in his cell or in his garden, and that rather than resisting he reasoned with them, so that they repented and reformed their lives. Because his books were his only possession and a recurring temptation to thieves, he is said to have sold the manuscripts and distributed the money to the poor.
These episodes are the basis for his being invoked in connection with theft and with the conversion of wrongdoers, and they account for the description of him as one who overcame thieves by gentleness.