The building of this temple is described as the decree of God; and, as the decree of a Persian king, or a series of decrees of a Persian king. The same act is being described as having been done by God and by man. Man does it: God does it through men. And that is what Ezra is saying here. The building of this temple was in one sense the decree of King Darius, but in another sense—and it is the exact same word—it was the decree of almighty God.1
Derek W. H. Thomas
14 And the elders of the Jews built and prospered through the prophesying of Haggai the prophet and Zechariah the son of Iddo. They finished their building by decree of the God of Israel and by decree of Cyrus and Darius and Artaxerxes king of Persia;