2:16 profane. That is, “ungodly” or “unholy.”

2:16 vain babblings. See I Timothy 6:20, where Paul identifies “profane and vain babblings” as related to “science falsely so called,” referring essentially to pantheistic evolutionary philosophy.

2:17 canker. This could be an ulcer or any ulcerating sore, even a cancer.

2:17 Hymenaeus and Philetus. Hymenaeus means “singing man” and Philetus means “friendly man.” These names may well suggest the characters of these two blasphemers (see note on I Timothy 1:20). It is often true that the most effective subverters of God’s Word of truth are men who outwardly seem to be very smooth and charming (compare II Corinthians 11:13-15).

2:18 overthrow the faith. The implication of this phrase refers to those who were corrupting such vital truths as in Romans 6:5 and Colossians 3:1-3, in addition to denying the great promises of the future resurrection when Christ returns (e.g., I Thessalonians 4:16-17).

2:19 this seal. This phrase is quoted from Numbers 16:5, though in a different context. In the church, built upon God’s true foundation (Christ and His Word) the Lord identifies those who belong to Him as those who believe on the name of Christ and therefore depart from iniquity.