Orthodox believers mark Holy Trinity Day
Patriarch Aleksy II held a service in Russia's spiritual centre, Holy Trinity Church in the town of Sergiyev Posad.
The Trinity glorifies God in three forms – the Father, the Son and the Holy Spirit. The celebration marks the descent of the Holy Spirit onto the Christ's apostles fifty days after his resurrection.
Followers believe God put flames around the apostles which gave them the ability to speak different languages and preach Christ's teachings around the world. That's why it's also thought Holy Trinity Day marks the birth of organised Christianity.