Sometimes a translation can err not so much by mistranslating a word as by giving an inappropriate connotation, which can then be a springboard for mistaken exegesis. 2 Corinthians 4:7 is such a verse:
Ἔχομεν δὲ τὸν θησαυρὸν τοῦτον ἐν ὀστρακίνοις σκεύεσιν, ἵνα ἡ ὑπερβολὴ τῆς δυνάμεως ᾖ τοῦ θεοῦ καὶ μὴ ἐξ ἡμῶν·
The first clause is usually translated, “We have this treasure in vessels of clay.” But there is a good Greek word for “clay” (πηλός), as well as many other words for mud, dirt, etc. If Paul were wanting to stress the earthy, dirty, material nature of the vessels, he would have used one of these words. Instead, the word he uses is ὀστρακίνοις, cognate with ִὀστρακόν, a potsherd. Paul means that we are weak and fragile.
This makes sense in Paul’s context, where our weakness is compared with God’s strength: we are given treasure in pottery vessels “so that the superlative power might be God’s, and not from us.” The point is not so much the composition of the vessel (that it is made of earth), as the fragility and weakness of it.
Recall that a potter’s vessel is a standard Biblical image of fragility (Psalm 2:9). The verses that follow 2 Corinthians 4:7 become even more vivid in this light: “we are afflicted…perplexed…persecuted…struck down…” We are to picture a fragile ceramic pot receiving a frightful buffeting, and somehow not being broken because it is preserved by the power of God.