The feast of the Holy Trinity (Holy Trinity Day) is a time when the Orthodox Church celebrated Trinity of the Godhead. This is one of the favorite holidays of Russian people. However, not always this celebration is called "the Holy Trinity".

In the Charter of the Church there is another naming of this feast of the Holy Pentecost. In all the liturgical books, the feast of the Trinity accompanies this name. Why is Pentecost? In accordance with the gospel description, on the fiftieth day after the resurrection of Jesus Christ to the Holy apostles, the Holy Ghost came. This was a phenomenon of the third Person of the Holy Trinity. This day became the birthday of the Church (the birthday of the Church - another name for the feast of the Holy Trinity very favorite people). It turns out that Pentecost is the name, indicating the time of the historical event. Until now, the Holy Trinity Day (Pentecost) is celebrated the Orthodox Church on the 50th day after Easter.

Another name for the feast of the Holy Trinity is "the Descent of the Holy spirit on the apostles." This naming indicates not on time, and the event itself.

It is also worth noting that the day after the feast of the Holy Trinity separately dedicated to the Holy Spirit. In the Church calendar it is called Spirit day. According to ancient folk tradition on the Monday after Pentecost is called the birthday of the mother of the earth.