From the early Church Fathers to now.
2 Patristic · 2 Jewish · 1 Catholic · 1 Reformed
“And justice shall be the girdle of his loins: and faith the girdle of his reins.”
“At all times let us stand firm, but especially now, although many afflictions overtake us and many heretics are furious against us. Let us then, my beloved brothers, celebrate with thanksgiving the holy feast that now draws near to us, "girding up the loins of our minds," like our Savior Jesus Christ, of whom it is written, "Righteousness shall be the girdle of his loins, and faithfulness the girdle of his reins."”
“He is not speaking of a literal, physical belt, for all the language in this passage he employs in a spiritual sense.”
“And righteousness shall be the girdle of his loins Jonathan [renders:] And the righteous shall surround him; i.e., they will cleave to him like a girdle.”
“And righteousness shall be, etc. And uprightness will never depart from him in all his doings.”
“Reins. He shall possess these virtues, performing his promises with the strictest fidelity. (Calmet)”
“righteousness . . . girdle-- (Rev 1:13; Rev 19:11). The antitypical High Priest (Exo 28:4). The girdle secures firmly the rest of the garments (Pe1 1:13). So "truth" gives firm consistency to the whole character (Eph 5:14). In Isa 59:17, "righteousness" is His breastplate.”
The in-app commentary runs from the Fathers to the early-modern record, then stops — that's where the public-domain sources end, not where the reading does. For the modern reading, follow the sources directly.