St. Mesrob was born in 361 in Hatzegatz, Armenia, in his early years mastering Greek, Persian, and Syriac in addition to his native Armenian and serving at the Armenian royal court. He was later ordained to the priesthood and preached in the province of Koghtn in the late 390s. It was during his missionary service in Koghtn that St. Mesrob felt the great need of the Armenian language for an alphabet. He consequently sought and received the blessing of Catholicos St. Sahag for the creation of an alphabet.
After spending a great deal of time traveling to research the alphabets of the region, St. Mesrob is said to have developed a rough framework of an alphabet for Armenian. It did not fit the sounds of the Armenian language, however, and was unusable. One day the Saint was meditating in a cave when he had a vision in which the hand of God wrote an alphabet in letters of fire on the cave wall, each letter corresponding to the unique sounds of the Armenian language. When St. Mesrob returned to Echmiadzin with a copy of the divine alphabet he was received with great joy and honor by both the Armenian king and Catholicos Sahag.
St. Mesrob subsequently spent many years translating works into Armenian and composing literary and ecclesiastical works in the language, giving it its first literary works. He is said to have first translated Proverbs 1:2, "To know wisdom and instruction; to perceive the words of understanding." St. Mesrob was also invited to the Orthodox Christian kingdoms of Imereti (modern day eastern Georgia) and Arran ('Caucasian Albania,' now Azerbaijan) to develop alphabets for the Georgian and Arranian languages.
Following his death in 438 St. Mesrob was buried in Oshagan, where a cathedral was later built in his memory. His tomb is preserved in the cathedral to the present day.
St. Mesrob Mashtots is commemorated on 19 February.