He shall judge your people with righteousness, and your poor with justice.
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Augustine of Hippo
3. Next there followeth, "To judge Thy people in justice, and Thy poor in judgment" (ver. 2). For what purpose the royal Father gave to the royal Son His judgment and His justice is sufficiently shown when he saith, "To judge Thy people in justice;" that is, for the purpose of judging Thy people. Such an idiom is found in Salomon: "The Proverbs of Salomon, son of David, to know wisdom and discipline:" that is, the Proverbs of Salomon, for the purpose of knowing wisdom and discipline. So, "Thy judgment give Thou, to judge Thy people:" that is, "Thy judgment" give Thou for the purpose of judging Thy people. But that which he saith before in, "Thy people," the same he saith afterwards in, "Thy poor:" and that which he saith before in, "in justice;" the same afterward in, "in judgment:" according to that manner of repetition. Whereby indeed he showeth, that the people of God ought to be poor, that is, not proud, but humble. For, "blessed are the poor in spirit, for theirs is the kingdom of Heaven." In which poverty even blessed Job was poor even before he had lost those great earthly riches. Which thing for this reason I thought should be mentioned, because there are certain persons who are more ready to distribute all their goods to the poor, than themselves to become the poor of God. For they are puffed up with boasting wherein they think their living well should be ascribed to themselves, not to the grace of God: and therefore now they do not even live well, however great the good works which they seem todo. ...
4. But seeing that he hath changed the order of the words (though he had first said, "O God, Thy judgment to the King give Thou, and Thy justice to the King's Son," putting judgment first, then justice), and hath put justice first, then judgment, saying, "To judge Thy people in justice, and Thy poor in judgment:" he doth more clearly show that he hath called judgment justice, proving that there is no difference made by the order in which the word is placed, because it signifieth the same thing. For it is usual to say "wrong judgment" of that which is unjust: but justice iniquitous or unjust we are not wont to speak of. For if wrong and unjust it be; no longer must it be called justice. Again, by putting down judgment and repeating it under the name of justice, or by putting down justice and repeating it under the name of judgment, he clearly showeth that he specially nameth that judgment which is wont to be put instead of justice, that is, that which cannot be understood of giving an evil judgment. For in the place where He saith, "Judge not according to persons, but right judgment judge ye;" He showeth that there may be a wrong judgment, when He saith, "right judgment judge ye:" lastly, the one He doth forbid, the other He doth enjoin. But when without any addition He speaketh of judgment, He would at once have just judgment to be understood: as is that which He saith, "Ye forsake the weightier matters of the Law, mercy and judgment." That also which Jeremiah saith is, "making his riches not with judgment." He saith not, making his riches by wrong or unjust judgment, or not with judgment right or just, but not with judgment: calling not anything judgment but what is right and just.