Of the massacre of Thessalonica; the boldness of Bishop Ambrosius, and the piety of the Emperor
So both the archbishop and the emperor showed a mighty shining light of virtue. Both to me are admirable; the former for his brave words, the latter for his docility; the archbishop for the warmth of his zeal, and the prince for the purity of his faith.
On his return to Constantinople Theodosius kept within the bounds of piety which he had learned from the great archbishop. For when the occasion of a feast brought him once again into the divine temple, after bringing his gifts to the holy table he straightway went out. The bishop at that time was Nectarius, and on his asking the emperor what could possibly be the reason of his not remaining within, Theodosius answered with a sigh “I have learned after great difficulty the differences between an emperor and a priest. It is not easy to find a man capable of teaching me the truth. Ambrosius alone deserves the title of bishop.”
So great is the gain of conviction when brought home by a man of bright and shining goodness.
Source: Ecclesiastical History (New Advent)