“That he may send the Christ appointed for you, Jesus, whom heaven must receive until the time for restoring all the things about which God spoke by the mouth of his holy prophets long ago.” (Acts 3:20–21 ESV)

It’s quite obvious that from the earliest moment of the church, those who followed Jesus by faith believed that he would come again to restore all things.  He had ascended into heaven, but that was not the end of the story; the end of the story has yet to be accomplished, because the “time for restoring all things” is not at hand yet.  It will come.  We should anticipate it and watch for it.  Christ said that he would return, and he means what he says and will do what he has promised.