[Antoninus]

In the Orthodox tradition, humility has often been called the “mother of all virtues,” and pride has been named “the cause of all sin.” The wise and honest person is the one who is humble.....

Not just the Orthodox, my friend. Both Orthodox and Catholics venerate Pope St. Gregory the Great who said (in the above article) that humility is, "the mistress and mother of all virtues) way back in the early 7th century AD.

[Honorary Serb]

During Great Lent, we Orthodox celebrate the Liturgy of the Presanctified Gifts, a service attributed to Pope St. Gregory the Great!