There will be harmony between the two

Zechariah 6:9-15

The word of the Lord came to me: “Take silver and gold from the exiles Heldai, Tobijah and Jedaiah, who have arrived from Babylon. Go the same day to the house of Josiah son of Zephaniah. Take the silver and gold and make a crown, and set it on the head of the high priest, Joshua son of Jozadak. Tell him this is what the Lord Almighty says: ‘Here is the man whose name is the Branch, and he will branch out from his place and build the temple of the Lord. It is he who will build the temple of the Lord, and he will be clothed with majesty and will sit and rule on his throne. And he will be a priest on his throne. And there will be harmony between the two.’ The crown will be given to Heldai, Tobijah, Jedaiah and Hen son of Zephaniah as a memorial in the temple of the Lord. Those who are far away will come and help to build the temple of the Lord, and you will know that the Lord Almighty has sent me to you. This will happen if you diligently obey the Lord your God.”

V9 marks the end of the vision and introduces a word from God. Surprisingly the crown is given to Joshua the priest. It may be that the crown was placed first on the head of Joshua, then on the head of Zerubbabel - or that two crowns were made. Both men seem to be present. The king 'the Branch' - and the high priest work in harmony together. The New Testament sees the two roles become one in the person of Jesus.

Why?

Jesus is the king of authority and the high priest with honor. He is the branch of David. 

Those who are far away will come and help to build the temple of the Lord. Even it looks impossible but under the plan of the Lord, it will be done. Because it is the Lord Almighty who made it.

How?

Give thanks to the Lord, and obey His command. May the Lord be my wisdom, righteousness, holy and salvation.