The Monday after Pentecost Sunday, we Orthodox celebrate Holy Spirit Day.

When He came down and confused the tongues,
the Most High divided the nations;

but when He distributed the tongues of fire,
He called all people to unity.

Therefore, with one voice, we glorify the most-Holy Spirit.

(Hymn of the Feast)

For you were once darkness, but now you are light in the Lord. Walk as children of light (for the fruit of the Spirit is in all goodness, righteousness, and truth), finding out what is acceptable to the Lord.  And have no fellowship with the unfruitful works of darkness, but rather expose them. For it is shameful even to speak of those things which are done by them in secret. But all things that are exposed are made manifest by the light, for whatever makes manifest is light. Therefore He says:

(From the epistle for the day, Ephesians 5)