What does Luke 24:52 mean?

Jesus has ascended into heaven (Luke 24:51). The Holy Spirit has not yet come, but Jesus' followers have faith He will. And they know Jesus will return (Acts 1:11).

The larger group of disciples return to Jerusalem, to the temple. The temple is built on the site of David's tabernacle (2 Samuel 6:17). Jesus is the Messiah, the heir of David who will rule Israel. He's also God the Son. It's appropriate they go to the temple and praise God for fulfilling His promises to His people (Luke 24:53).

The nature of the move is significant. Forty days before, a large group of Jesus' followers were in a room in Jerusalem with the doors locked, afraid the Pharisees, scribes, elders, and chief priests would find them (John 20:19). Now, they boldly walk into the city—to the very territory of the priests. Soon, they will find themselves in a similar—if not the same—room on Pentecost. Luke describes what happens there: "And suddenly there came from heaven a sound like a mighty rushing wind, and it filled the entire house where they were sitting. And divided tongues as of fire appeared to them and rested on each one of them. And they were all filled with the Holy Spirit and began to speak in other tongues as the Spirit gave them utterance" (Acts 2:2–4).

After they receive the Holy Spirit, their boldness will grow. Peter and John will turn a healing into a proclamation about Jesus and the resurrection (Acts 3). Despite persecution and even beatings by the priests, the apostles will continue to return to the temple Mount to heal and preach Christ resurrected (Acts 5:12–42).