Jeremiah 13:7
Then I went to Euphrates, and digged, and took the girdle from the place where I had hid it: and, behold, the girdle was marred, it was profitable for nothing.
Cross-reference
In Jeremiah 13:10, the LORD explicitly says this evil people will be like the ruined loincloth — good for nothing.
Ezekiel 15:3-5 asks if vine wood is good for anything — same 'good for nothing' concept as the spoiled loincloth.
In Luke 14:34, salt that loses its saltiness becomes useless — just like this loincloth, something once good becomes worthless.
In Luke 14:35, the useless salt is thrown out — mirroring the discarded loincloth here, both fit only for rejection.
In Romans 3:12, Paul says all have become worthless — the same term used here for the loincloth, linking human sinfulness to ruin.
In Philemon 1:11, Onesimus goes from useless to useful — contrasting with this loincloth that remained ruined, showing transformation vs. unrepentance.