Thus says the Lord: Rejoice heartily, O daughter Zion,
shout for joy, O daughter Jerusalem!
See, your king shall come to you; a just savior is He, meek,
and riding on an ass, on a colt, the foal of an ass.
ZECHARIAH 9 : 9
Jesus found an ass and sat upon it, as it is written: "Fear no more, O daughter of Zion: see, your king comes, seated upon an ass's colt." - John 12:14-15
On the next day, when the great crowd that had come to the feast heard that Jesus was coming to Jerusalem, they took palm branches and went out to meet him, and cried out: "Hosanna! Blessed is he who comes in the name of the Lord, [even] the king of Israel." - John 12:12-13
His disciples did not understand this at first, but when Jesus had been glorified they remembered that these things were written about him and that they had done this for him. - John 12:16