When is the feast of Saint Sophia? (post-Pentecost in Greek Orthodox calendar)

When is the feast day of Saint Sophia?

The name of our cathedral is a translation of “Hagia Sophia” (Agia Sofia), which means Holy Wisdom. In the words of Saint Paul,
For Jews demand signs and Greeks seek wisdom, but we preach Christ crucified, a stumbling block to Jews and folly to Gentiles, but to those who are called, both Jews and Greeks, Christ the power of God and the wisdom of God. (1 Cor 1.23-25)
By tradition the feast day of churches of the Holy Wisdom is the Monday following Pentecost, the Monday of the Holy Spirit.
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