Introduction:
Zechariah, the son of Berechiah and grandson of Iddo, was a prophet and priest who ministered to the Jewish people during the post-exilic period, around 520-518 BC. His prophetic ministry coincided with that of Haggai, and both prophets encouraged the Israelites to rebuild the Temple in Jerusalem after their return from Babylonian exile. The Book of Zechariah is the eleventh book of the Twelve Minor Prophets in the Old Testament and is known for its apocalyptic visions, messianic prophecies, and calls for repentance and spiritual renewal.

Structure and Themes:
The Book of Zechariah is divided into two main sections: chapters 1-8 and chapters 9-14. The first section contains a series of eight night visions, symbolic actions, and oracles that focus on the immediate concerns of the Jewish community, such as the rebuilding of the Temple and the restoration of Jerusalem. The second section is more eschatological, containing prophecies about the coming of the Messiah, the future glory of Israel, and the ultimate triumph of God's kingdom.

Key Prophecies and Visions:

1. The Call to Repentance (Zechariah 1:1-6):
Zechariah begins his ministry with a call for the people to return to the Lord. He reminds them of the consequences faced by their ancestors due to disobedience and urges them to seek God earnestly.

“Therefore tell the people that this is what the LORD of Hosts says: ‘Return to Me, declares the LORD of Hosts, and I will return to you, says the LORD of Hosts.’” (Zechariah 1:3)

2. The Eight Night Visions (Zechariah 1:7-6:15):
These visions include the rider among the myrtle trees, four horns and four craftsmen, a man with a measuring line, the cleansing of Joshua the high priest, the golden lampstand and two olive trees, the flying scroll, the woman in a basket, and the four chariots. Each vision conveys messages of hope, divine protection, and the eventual triumph of God's purposes.

3. The Branch and the Temple (Zechariah 3:8-10; 6:12-13):
Zechariah introduces the figure of "the Branch," a messianic title, who will build the Temple of the Lord and rule as both priest and king.

“Hear now, O Joshua the high priest, you and your companions seated before you, who are symbolic of things to come: I am going to bring My servant, the Branch.” (Zechariah 3:8)

4. The Coming King (Zechariah 9:9-10):
Zechariah prophesies the coming of a humble and righteous king, riding on a donkey, a prophecy fulfilled in the New Testament with Jesus' triumphal entry into Jerusalem.

“Rejoice greatly, O Daughter of Zion! Shout in triumph, O Daughter of Jerusalem! See, your king comes to you, righteous and victorious, humble and riding on a donkey, on a colt, the foal of a donkey.” (Zechariah 9:9)

5. The Shepherd and the Betrayal (Zechariah 11:12-13):
Zechariah speaks of a shepherd who is rejected and valued at thirty pieces of silver, a prophecy that foreshadows Judas Iscariot's betrayal of Jesus.

“And I said to them, ‘If it seems good to you, give me my wages; but if not, keep them.’ So they weighed out my wages—thirty pieces of silver. And the LORD said to me, ‘Throw it to the potter,’ the magnificent price at which they valued Me. So I took the thirty pieces of silver and threw them into the house of the LORD to the potter.” (Zechariah 11:12-13)

6. The Pierced One (Zechariah 12:10):
Zechariah foretells a time when the inhabitants of Jerusalem will mourn for the one they have pierced, a prophecy seen as pointing to the crucifixion of Christ.

“Then I will pour out on the house of David and on the residents of Jerusalem a spirit of grace and prayer, and they will look on Me, the One they have pierced. They will mourn for Him as one mourns for an only child, and grieve bitterly for Him as one grieves for a firstborn son.” (Zechariah 12:10)

7. The Day of the LORD (Zechariah 14):
The final chapter describes the coming "Day of the LORD," a time of divine intervention, judgment, and the establishment of God's kingdom. It envisions the Lord as king over all the earth and the ultimate restoration and holiness of Jerusalem.

Significance:
Zechariah's prophecies are significant for their rich symbolism and messianic expectations. They provide hope and encouragement to the post-exilic community and point forward to the coming of the Messiah, Jesus Christ, who fulfills many of Zechariah's predictions. The book emphasizes themes of repentance, divine sovereignty, and the ultimate victory of God's kingdom, resonating with both historical and eschatological dimensions.