Although the Gospels often give the impression that Jesus ascended into heaven on Easter evening because, for example, they tend to compress the post-Resurrection events into a single day (e.g., Mark 16:9-19), the Book of Acts (written by Luke) makes clear that Jesus appeared to the disciples for a period of forty days before his Ascension into heaven (Acts 1:3). Ascension Thursday celebrates Christ’s ascension into heaven after that forty-day period, although in the U.S. the celebration is often transferred to the nearest Sunday.
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