What is "Parshegen ha'Nishtavan"?
Rashi: The explanation of the letter.
Malbim: The king's command was in Persian. It was translated into Arame'ic, which was spoken in Surya. The king's appointees translated it. They testified that their translation Nishtavan (equals) the original text.
What do we learn from "Sofer Divrei Mitzvos Hashem"?
Malbim: This explains why he is called Sofer. It is not due to his trade (a scribe). Rather, he counts matters of Mitzvos Hashem. He counts letters of the Torah and makes a fence for tradition. He also made a fence in copying other Kisvei ha'Kodesh, to cleanse them from any dross (error). He also counted words of oral Torah; this is included in "Chukim".
What are "Chukav Al Yisrael"?
Rashi: The Chukim that Hashem commanded Yisrael to guard them.
Malbim: "Al Yisrael" refers back to the letter that the king gave to Ezra, about Yisrael, for their needs.
