Gregory was born in Tmkaberd in Georgia or Vayots Dzor in Siunik.

[1] Gregory was a faithful Miaphysite, at a time when the Armenian church was building relations with the Dyophysite Roman Catholic Church.

He wrote against uniting the Armenian church with Rome.

[2] In 1397, during perpetual invasions by the Timurids, he completed the Book of Questions, a basic and comprehensive theological outline.

[2] A monument to Tatevatsi was unveiled on October 16, 2010 in Goris, Armenia.