What does Luke 19:30 mean?
A crowd of disciples have left Jericho with Jesus (Luke 18:35) and are approaching Jerusalem from the east, directly opposite the Temple Mount. They are on the eastern slope of the Mount of Olives at Bethphage (Matthew 21:1).Jesus knows exactly where the donkey and its mother are tied (Matthew 21:2) and what those nearby will say (Luke 19:31). No note is made if the disciples paid for the use of the donkey, but it may have been an animal available for hire.
Matthew 21:2 mentions that the colt is with his mother and the mother comes with the disciples, as well (Matthew 21:7). This addition isn't a contradiction, it just provides more detail. Matthew 21:5 explains that Jesus is fulfilling Old Testament prophecy: the king of Zion is humble and rides a donkey (Zechariah 9:9). This is an image the disciples won't recognize until later (John 12:16).
That the donkey is still with its mother and that the mother accompanies it suggests it is quite young. That has led some to fear it was too immature to hold Jesus' weight. Whatever the age and condition of the colt, we can be sure its Creator and Sustainer made sure it was strong enough for the job (Colossians 1:17).