[1] Grigor III held office as catholicos for a little more than fifty years, and his younger brother Nerses assisted him greatly during this time.
Pahlavuni was able to maintain peace within the Cilician Kingdom and the catholicosate during a time of instability due to raids from foreign invaders.
In November 1139 he participated together with his brother Nerses in the legatine council convened by the papal legate Alberic of Ostia in the cathedral of Antioch.
[2] Here he attended another synod in the Templum Domini in April 1141 where he made a profession of faith and promised to restore union with Rome, which was achieved by the end of the century.
[2] Because of these foreign invasions, Grigor III chose to seek refuge and moved the catholicosate two times: once in 1116 from Karmir Vank' at Kaysun to its new location in Tsovak, and again in 1148 or 1150 to Hromgla, which he acquired from Beatrice from Turbessel.