The prophecy:
“Rejoice greatly, O daughter of Zion!
 Shout in triumph, O daughter of Jerusalem!
 Behold, your king is coming to you;
 He is just and endowed with salvation,
 Humble, and mounted on a donkey,
 Even on a colt, the foal of a donkey.”  Zechariah 9:9

The fulfillment:
“…When they heard that Jesus was coming to Jerusalem, took the branches of the palm trees, and went out to meet Him, and began to cry out, ‘Hosanna!  
Blessed is He who comes in the name of the LORD!
The King of Israel.’  
Then Jesus, When He had found a young donkey, sat on it; as it is written: ‘Fear not, daughter of Zion; 
Behold, your King is coming, 
Sitting on a donkey’s colt.’”  John 12:12-15

You will find this account in all four Gospels: Matthew 21:1-11, Mark 11:1-11, Luke 19:28-38, John 12:12-15.  (Read all of them for the added information they give to fill out the whole scene.) 

This is the day we call ‘Palm Sunday’ when Christians celebrate the triumphal entry of Jesus into Jerusalem.  The people were there at that time for the Feast of Passover. 
Note:
(Read Exodus Chapter 12 for God’s instructions for Passover through Moses.)  
Concerning the lamb to be sacrificed,
“Your lamb shall be without blemish, a male of the first year.  You may take it from the sheep or the goat.”  Exodus 12:5
Only Almighty God; Father, Son and Holy Spirit, knew who this spotless and perfect Lamb would be.  The shed blood of the Lamb of God was the plan for salvation from before the foundation of the world!  
Scripture tells us that Jesus is,
“…The Lamb slain from the foundation of the world.”  Revelation:13:8

The prophecy of Isaiah 53:7 tells us,
“He was oppressed and He was afflicted,
 Yet He did not open His mouth;
 Like a lamb that is led to slaughter,
 And like the sheep that is silent before its shearers,
 So He did not open His mouth,”

In Matthew 27:12-14 that prophecy was fulfilled:
“And while He was being accused by the chief priests and elders, He answered nothing.  Then Pilate said to Him, ‘Do You not hear how many things they testify against You?’  And He answered him not a word…”

In John 1:29 John the Baptist declares,
“Behold, the Lamb of God who takes away the sin of the world!’”

And we see in 1 Peter 1:18-19this truth,
“Knowing that you were  not redeemed with perishable things…but with the precious blood, as of a lamb unblemished and spotless, the blood of Christ!”

Christ, the Lord, is forever the Lamb of God as we see through the Apostle John’s eyes in verses of the Revelation,
“And I saw between the throne (with the four living creatures) and the elders a Lamb standing, as if slain…”  Revelation 5:6

“And I saw when the Lamb broke one of the seven seals, and I heard one of the four living creatures saying with a voice of thunder, ’Come’.”  Revelation 6:1

“After these things I looked and behold, a great multitude, which no one could count, from every nation and all tribes and peoples and tongues, standing before the throne and before the Lamb, clothed in while robes and palm branches were in their hands and they cry out with a loud voice, saying, ‘Salvation belongs our God who sits on the throne, and to the Lamb.’”  Revelation 7:9-10

Speaking of the Holy City, John says,
“And I saw no temple in it, for the Lord God, the Almighty, and the Lamb are its temple.  And the city has no need of the sun or the moon to shine upon it, for the glory of God has illumined it, and its lamp is the Lamb.” Revelation 21:22-23
Jesus is the Passover Lamb!  Hebrews 10:1-19 gives the picture of the One perfect sacrifice for sin and His  obedience,
“Then He said, ‘Behold I have come to do Thy will.’  He takes away the first order to establish the second.  By this we have been sanctified through the offering of the body of Jesus Christ once for all.”  Vs. 9-10
And Vs. 12,
“…He, having offered one sacrifice for sins for all time, sat down at the right hand of God.”

Christ Jesus is THE glorious Lord of all!  All praise, honor and glory belongs to Him.  How awesomely wonderful is He!  Believers, beloved of Christ, let us give thanks to God for this life we now have in Christ!  Amen