Righteousness and justice are the habitation of your throne: mercy and truth shall go before your face.
Read Chapter 89
Augustine of Hippo
15. "Righteousness and judgment are the preparation of Thy seat" (ver. 14). Thy righteousness and judgment will appear in the end: they are now hidden. Of Thy righteousness it is treated in another Psalm, "on the hidden things of the Son." There will then be a manifestation of Thy righteousness and judgment: some will be set on the right, others on the left hand: and the unbelieving will tremble, when they see what now they mock at, and believe not: the righteous will rejoice, when they shall see what they now see not, yet believe. "Righteousness and judgment are the preparation of Thy seat:" especially in the Day of Judgment. What then now? "mercy and truth go before Thy face." I should fear the preparation of Thy seat, Thy justice, and Thy coming judgment, did not mercy and truth go before Thee: why should I at the end fear Thy righteousness, when with Thy mercy going before Thee Thou blottest out my sins, and by showing forth Thy truth fulfillest Thy promises? "Mercy and truth go be...
Preparation. Hebrew, "basis. "
Face. Like guards. (Menochius)
He extols the mercy, and still more the fidelity of God. (Calmet)
Whether he punished, or reward, all tends to promote his glory, and is perfectly just. (Worthington)