Expositor's Bible Commentary Commentary 2 Peter 2:21

"For it were better for them not to have known the way of righteousness, than, after knowing it, to turn back from the holy commandment delivered unto them." — 2 Peter 2:21 (ASV)

Peter now underlines the seriousness of apostasy. The “sacred commandment that was passed on to them” evidently refers to the authoritative, apostolic message of the Christian faith (cf. 1 Corinthians 15:3). It is the entire Christian message with an emphasis on the ethical demands of our Lord.