phtheiro describes bringing ruin or damage, whether by corrupting conduct and minds or by destroying persons.

The attested uses chiefly describe destruction or ruin, including the destruction of a person who destroys God’s temple and the ruin awaiting hostile figures. In other clauses, the term marks corrupting influence or deterioration: bad company affects morals, minds may be led away, the old self is being corrupted, and the earth is corrupted.

1. Bring destruction or ruin · dominant

   In 1 Corinthians 3:17, the two present active singular forms occur in the warning that a person who destroys God’s temple will in turn face God’s destruction. The APB also places the term in clauses of denied harm in 2 Corinthians 7:2 and of destruction in 2 Peter 2:12 and Jude 1:10.

   1 Corinthians 3:172 Corinthians 7:22 Peter 2:12Jude 1:10
2. Corrupt or spoil a person or setting · common

   In 1 Corinthians 15:33, the present active plural form occurs in the maxim about bad company and good morals. In 2 Corinthians 11:3 the aorist passive subjunctive concerns minds that might be corrupted away from openness and purity; Ephesians 4:22 describes the old self as being corrupted, and Revelation 19:2 says the great prostitute corrupted the earth.

   1 Corinthians 15:332 Corinthians 11:3Ephesians 4:22Revelation 19:2

In the Anselm Project Bible: Across the verses, the APB uses “destroys,” “harmed,” “corrupts,” “corrupted,” and “being corrupted.” These variations show the clauses’ presentation rather than fixed English equivalents for each form.