What is the meaning of Titus 1:15?

* The two F.O.G. Bibles & Commentary below are currently a work in progress.

To the pure, all things are pure; but to the defiled and unbelieving, nothing is pure. Indeed, both their minds and their consciences are defiled.

Berean Standard Bible (BSB)

To the pure, all things are pure; but to those who are defiled and unbelieving, nothing is pure; but both their mind and their conscience are defiled.

World English Bible (WEB)

Unto the pure{G2513} all things{G3956} are pure{G3303}{G2513}: but{G1161} unto them that are defiled{G3392}{(G5772)} and{G2532} unbelieving{G571} is nothing{G3762} pure{G2513}; but{G235} even{G2532} their{G846} mind{G3563} and{G2532} conscience{G4893} is defiled{G3392}{(G5769)}.

Strong's King James

(15) To the pure, everything is pure but to those who are defiled and unbelieving, nothing is pure, yet their mind and their conscience are defiled.

The F.O.G*

[15] To those whose hearts are pure, everything is pure. But to those corrupted by unbelief, nothing is pure—their minds and consciences are thoroughly contaminated.

The F.O.G Paraphrase

all things, indeed, are pure to the pure, and to the defiled and unstedfast is nothing pure, but of them defiled are even the mind and the conscience;

Young's Literal Translation