The Ascension of Our Lord, which occurred 40 days after Jesus Christ rose from the dead on Easter Sunday, is the final act of our redemption that Christ began on Good Friday. On this day, the risen Christ, in the sight of His apostles, ascended bodily into Heaven (Luke 24:51; Mark 16:19; Acts 1:9-11).
The reality of the Ascension is so important that the creeds (the basic statements of belief) of Christianity all affirm, in the words of the Apostles' Creed, that "He ascended into heaven, sits at the right hand of God the Father almighty; from thence He shall come to judge the living and the dead." The denial of the Ascension is as grave a departure from Christian teaching as is denial of Christ's Resurrection.
Christ's bodily Ascension foreshadows our own entrance into Heaven not simply as souls, after our death, but as glorified bodies, after the resurrection of the dead at the Final Judgment. In redeeming mankind, Christ not only offered salvation to our souls but began the restoration of the material world itself to the glory that God intended before Adam's fall.
The Feast of the Ascension marks the beginning of the first novena, or nine days of prayer. Before His Ascension, Christ promised to send the Holy Spirt to His apostles. Their prayer for the coming of the Holy Spirit, which began on Ascension Thursday, ended with the descent of the Holy Spirit on Pentecost Sunday, ten days later.