Many Arminians point to 2 Peter 2:20–21 as proof that a true believer can lose their salvation:

“For if, after they have escaped the defilements of the world through the knowledge of our Lord and Savior Jesus Christ, they are again entangled in them and overcome, the last state has become worse for them than the first. For it would have been better for them never to have known the way of righteousness than after knowing it to turn back from the holy commandment delivered to them.”

But interestingly, they often stop short of quoting the very next verse:

“The dog returns to its own vomit, and the sow, after washing herself, returns to wallow in the mire.” (v.22)

The point is unmistakable: these individuals were never transformed in nature. A dog may clean itself, but it remains a dog. A pig may be washed, but it is still a pig. These metaphors reinforce Peter’s central argument—they were never sheep. Their outward change was temporary and superficial, not the inward renewal of a regenerate heart.

It’s clear, then, that Peter is not speaking of true, born-again believers, but of false professors—those who had a surface-level association with Christ. They may have escaped certain outward sins and embraced some moral reform “through the knowledge of Christ,” but there is no indication they were sealed by the Spirit, born again, or truly united to Christ by saving faith.

If a truly regenerate person could fall away and be lost, then Christ’s ongoing intercession (Hebrews 7:25), the Spirit’s sealing (Ephesians 1:13), and the Father’s electing love (Romans 8:29–30) would all be rendered uncertain—dependent not on God’s grace, but on human effort. That’s not the gospel; that’s spiritual probation. Scripture teaches that those whom God saves, He keeps. As 1 Peter 1:5 declares, true believers are “kept by the power of God through faith,” not by their own ability to stay faithful apart from grace.