He was still of a young age and according to the chronicler Smbat Sparapet 'he did not display the same obedience to everyone as previously when he was under a tutor, rather he ruled the patriarchy in a willful manner, as his mother's brother wished'.
This caused envy amongst the more senior clergymen and brought many charges against him implying that he was not capable of being Catholicos.
They brought these claims to Prince Levon I of Armenia many times until he relented and had Gregory imprisoned in his palace at Hromgla.
He took linen and hung it out to descend from the fortress one night but fell to his death when the rope broke.
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