C. F. Keil and Franz Delitzsch on Ezra 1:3

Ezr 1:3

In conformity with the command of God, Cyrus not only invites the Jews to return to Jerusalem, and to rebuild the temple, but also requires all his subjects to assist the returning Jews, and to give free-will offerings for the temple. מי בכם, who among you of all his people, refers to all those subjects of his realm to whom the decree was to be made known; and all the people of Jahve is the whole nation of Israel, and not Judah only, although, according to Ezr 1:5, it was mainly those only who belonged to Judah that availed themselves of this royal permission. עמּו אלהיו יהי, his God be with him, is a wish for a blessing: comp. Jos 1:17; 1 Esdras 2:5, ἔστω; while in 2Ch 36:23 we find, on the other hand, יהוה for יהי. This wish is followed by the summons to go up to Jerusalem and to build the temple, the reason for which is then expressed by the sentence, ”He is the God which is in Jerusalem.”