May the God … is a curse formula. A curse is a call upon a power that is greater than oneself to cause harm or evil to befall someone. Here Darius’s curse is meant to protect what is precious and important to him.
Who has caused his name to dwell there signifies God’s ownership of the Temple. In his curse Darius calls upon the God of the Jews who made his name to dwell in Jerusalem (see Deut 12.11). Good News Translation restructures here (“who chose Jerusalem as the place where he is to be worshiped”) in order to convey the meaning of this Old Testament expression, but in so doing it loses the reference to the name of God. God’s name is a very powerful Old Testament symbol for the identity of the God of Israel (see the comments on Ezra 5.1).
To overthrow means to “cause the downfall” (New Jewish Publication Society’s Tanakh) of a political power. Chouraqui translates this using the stronger term “exterminate.”
Put forth a hand is a metaphor for undertaking to do something. Some versions retain the metaphor (New International Version, Osty-Trinquet, Traduction œcuménique de la Bible), while Bible de Jérusalem translates “undertakes.” New Jerusalem Bible translates it as “dares.”
At the end of the reply by King Darius is the equivalent of his signature: I, Darius, make a decree. This may need to be restructured, for example, “It is I Darius who makes this decree” (see Parole de Vie). The king’s seal would have been applied on the original document.
Let it be done with all diligence: The decree is to be carried out with all diligence, that is, quickly and exactly/thoroughly. Urgency and carefulness are both implied in this expression (see Ezra 5.8, where Revised Standard Version renders it “diligently”). Osty-Trinquet translates “Let it be carried out punctually!” Traduction œcuménique de la Bible says “let it be done exactly so!” Chouraqui has “It will be carried out with faithfulness.” This is Darius’s formal closing statement to his decree.
Quoted with permission from Noss, Philip A. and Thomas, Kenneth J. A Handbook on Ezra. (UBS Helps for Translators). New York: UBS, 2005. For this and other handbooks for translators see here .