What does Luke 19:31 mean?
Jesus is at or near Bethphage (Matthew 21:1) on the Mount of Olives. A great crowd of disciples surrounds Him. Some have been with Him since the beginning, some came with Him from Galilee, and some from Bethany witnessed or heard how He had raised Lazarus from the dead. He is sending two disciples—Luke does not say which ones—into a village to obtain a donkey for His entrance into Jerusalem. Jesus specifically wants a donkey colt no one has ridden, along with its mother (Matthew 21:2; Mark 11:2).Assuming Jesus had not made some previous arrangement with the donkeys' owners, He has shown His supernatural abilities by telling the disciples where to find the donkeys. Now, He tells them what will happen when they untie the animals. We don't know who the donkeys belong to or who it is that will challenge the disciples. People did often keep animals to rent to travelers, but we don't know whether the disciples paid.
The point of the gesture is the donkey, itself. Although the disciples won't realize the connection until later (John 12:16), Zechariah 9:9 describes the king of the Jews: "Behold, your king is coming to you; righteous and having salvation is he, humble and mounted on a donkey, on a colt, the foal of a donkey." The crowd may think that Jesus is planning to expel the Romans and give Israel political independence. His goal is much grander: He is going to die for His people and rise again.
Mark and Luke record Jesus' words a little differently. Mark 11:3 says, "If anyone says to you, 'Why are you doing this?'" Luke's version has Jesus say, "Why are you untying it?" Though some claim this is a contradiction, it's merely the difference between a direct quote or a paraphrase. Scholars call these "ipsissima verba" and "ipsissima vox," respectively. Ipsissima verba means "the very words" and applies to word-for-word records. Ipsissima vox means "the very voice," or a summarized version of the words carrying the same meaning. Both Luke and Mark convey the point Jesus is making, which is not dependent on the exact phrasing He used.