Happy Easter Everyone. Easter, the principal festival of the Christian church year, celebrates the Resurrection of Jesus Christ on the third day after his Crucifixion. The origins of Easter date to the beginnings of Christianity, and it is probably the oldest Christian observance after the Sabbath (observed on Saturday). Later, the Sabbath subsequently came to be regarded as the weekly celebration of the Resurrection. Meanwhile, many of the cultural historians find, in the celebration of Easter, a convergence of the three traditions – Pagan, Hebrew and Christian.