Ascension, in Christian belief, the ascent of Jesus Christ into heaven on the 40th day after his Resurrection (Easter being reckoned as the first day). The Feast of the Ascension ranks with Christmas, Easter, and Pentecost in the universality of its observance among Christians. The feast has been celebrated 40 days after Easter in both Eastern and Western Christianity since the 4th century. Prior to that time, the Ascension was commemorated as a part of the celebration of the descent of the Holy Spirit at Pentecost.
The meaning of the Ascension for Christians is derived from their belief in the glorification and exaltation of Jesus following his death and Resurrection, as well as from the theme of his return to God the Father. Thus, the Gospel According to John uses both the sayings of Jesus and his post-Resurrection appearances to indicate a new relationship between Jesus and his Father and between him and his followers, rather than a simple physical relocation from earth to heaven.
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