His contemporary Hovhannes Draskhanakerttsi described him as a honorable man who was selected from the Catholicos's household by Prince Ashot I of Armenia to succeed Patriarch Zakaria.
This enraged the sparapet Abas who is said to have spread false rumors about the Catholicos in an attempt to bring him down.
Mashtots wrote a long letter in response, rejecting the offer to rebel against the Catholicos and chided Abas for his attempt.
Hovhannes Draskhanakerttsi reports at this point Abas was struck by an illness and died, as if by divine wrath, and the other conspirators repented to the Catholicos out of fear.
Afshin attempted to get George to bring King Smbat to him for a discussion, but the nakharars advised him not to go for fear of a trap.