Then returned they unto Jerusalem from the mount called Olivet, which is from Jerusalem a sabbath day's journey.

ACTS 1:12KJV
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What does Acts 1:12 mean?

Acts 1:12 describes how Jesus’ followers returned to Jerusalem from the Mount of Olives after witnessing His ascension, noting that the distance was about a “sabbath day’s journey” from the city. This phrase means the Mount of Olives was close enough to Jerusalem that it could be reached on foot without breaking Sabbath travel restrictions.

The book of Acts is written by Luke and is describing what the apostles did immediately after Jesus was taken up into heaven. The “sabbath day’s journey” refers to a traditional limit for travel on the Sabbath, about three-quarters of a mile (a distance based on Jewish law). The verse sets the scene for the group’s return to Jerusalem, where they would wait together as Jesus had instructed them.