“As to the soul, we must develop her power by faith and knowledge” — attributed to St. Matthias by Clement of Alexandria
In the nine days of waiting between Jesus’s ascension and the day of Pentecost, the disciples remained together in prayer. During this time, Peter reminded them that the death of Judas had left the fellowship of the Twelve with a vacancy. Two men were nominated, Joseph called Barsabbas, who was surnamed Justus, and Matthias. After prayer, the disciples cast lots, and Matthias was chosen to join them. And with that, Matthias disappears from recorded history.
Clement of Alexandria, however, included several sayings of St. Matthias in his writings, and Abbot Gueranger, OSB comments on these in The Liturgical Year.
We must subject the body to the spirit in order to be restored to the image and likeness of God unto which we were created. But the soul has inclinations towards evil…what is to be her protection? Faith and knowledge. Faith humbles her, and then exalts and rewards her; and the reward is knowledge. — The Liturgical Year, Abbot Gueranger O.S.B., adapted