Fr. Dumitru Staniloae explains in his book, Orthodoxy, Life in the Resurrection, the importance of the Resurrection for the Orthodox Church, stating that:
“The deepest foundation of the hope and joy which characterise Orthodoxy and which penetrate all its worship is the Resurrection. Easter, the centre of Orthodox worship, is an explosion of joy, the same joy which the disciples felt when they saw the risen Saviour. It is the explosion of cosmic joy at the triumph of life, after the overwhelming sorrow over death – death which even the Lord of life had to suffer when he became man. ‘Let the heavens rejoice and the earth exult, and let all the world invisible and visible keep holiday, for Christ our eternal joy is risen’ All things are now filled with the certainty of life, whereas before all had been moving steadily towards death. Orthodoxy emphasises with special insistence the faith of Christianity in the triumph of life”.
St Vasilios Greek Orthodox Church 