“For whoever lacks these qualities is so nearsighted that he is blind, having forgotten that he was cleansed from his former sins.”
– 2 Peter 1:9
In verses 5-8*, Peter discusses that clinging to Christian virtues is an effort to “supplement your faith” which “keep[s] you from being ineffective or unfruitful in the knowledge of our Lord Jesus Christ”. The New Testament repeats the message that Jesus has done the work to save us and continues to do so, in which we have a big part to play. If we simply declare we are Christian and do not live according to what Jesus has called us to do, then we are faithless and useless (James 2: 20*). The one who lacks these qualities mentioned by Peter, is spiritually blind and has forgotten that he was cleansed from his sins (Titus 3: 5-7*). This lack of fruitfulness could exist because a person’s “cleansing” was merely an external reformation that did not come from a truly changed heart. Jesus calls us to circumcise our hearts by accepting a renewal of ourselves from the inside – changing our way of life and turning away from sin (Jeremiah 4:4*, Romans 2: 29*). The verse in 2 Peter 1:9 could also be describing a genuine Christian who has fallen into serious error regarding the Christian life. Only God knows the person’s true status and heart (2 Timothy 2: 19*).
However, Peter is warning all followers of Christ to stay true to who we are as “Christians”, as those who work for His kingdom and look in all aspects of life to glorify Him. He expounds on this idea in 2 Peter 2:20-22* by highlighting tragic outcomes of those who confess to know Christ and then reject Him. Openly rejecting Christ when having claimed to have known Him is rejecting Christ’s grace, mercy, and everything He has done for you. Secondly, the knowledge and experience of a Christian life makes one more accountable before God (Luke 12:47-48*). Some people may think that these verses imply that true believers can lose their salvation. It is more likely that Peter is referring to people who appeared to be Christians externally, but then showed by their apostasy and their immoral behavior that they never truly belonged to Christ. We see this evidently happen in John 6:66, as followers abandon following Jesus when he declares that only true followers are those granted by the Father and circumcised in the heart. Those who truly follow Christ will never fall away because He holds us steadfast in faith by His grace (John 10:27-29*, Philippians 1:6).
Lastly, Peter refers to Proverbs 26:11 to visually illustrate the life one who continues to indulge in sin and claims that they are a true follower of Christ. To turn back and live in sin is as the “dog returns to its own vomit, and the sow, after washing herself, returns to wallow in the mire.” These people hold a mere disguise of one who is saved, but purposefully returning to sin and the rejection of Christ, demonstrate that they were never truly renewed.
The question we need to ask ourselves everyday is, “Am I true believer or am I merely a dog returning to his own vomit?”. Jesus calls us to look at ourselves and actively “repent and believe in the gospel” (Mark 1:15).
*2 Peter 1:5-8: “For this very reason, make every effort to supplement your faith with virtue,[a] and virtue with knowledge, and knowledge with self-control, and self-control with steadfastness, and steadfastness with godliness, 7 and godliness with brotherly affection, and brotherly affection with love. For if these qualities are yours and are increasing, they keep you from being ineffective or unfruitful in the knowledge of our Lord Jesus Christ.”
*James 2:20: “Do you want to be shown, you foolish person, that faith apart from works is useless?”
*Titus 3: 5-7: “he saved us, not because of works done by us in righteousness, but according to his own mercy, by the washing of regeneration and renewal of the Holy Spirit, 6 whom he poured out on us richly through Jesus Christ our Savior, so that being justified by his grace we might become heirs according to the hope of eternal life.”
*Jeremiah 4:4: “Circumcise yourselves to the Lord; remove the foreskin of your hearts, O men of Judah and inhabitants of Jerusalem; lest my wrath go forth like fire, and burn with none to quench it, because of the evil of your deeds.”
*Romans 2: 29: “But a Jew is one inwardly, and circumcision is a matter of the heart, by the Spirit, not by the letter. His praise is not from man but from God.”
*2 Timothy 2: 19: “But God’s firm foundation stands, bearing this seal: “The Lord knows those who are his,” and, “Let everyone who names the name of the Lord depart from iniquity.”
*Luke 12:47-48: “And that servant who knew his master’s will but did not get ready or act according to his will, will receive a severe beating. But the one who did not know, and did what deserved a beating, will receive a light beating. Everyone to whom much was given, of him much will be required, and from him to whom they entrusted much, they will demand the more.”
*2 Peter 2:20-22: “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. What the true proverb says has happened to them: “The dog returns to its own vomit, and the sow, after washing herself, returns to wallow in the mire.”
*John 6:66: “After this many of his disciples turned back and no longer walked with him.”
*John 10:27-29: “My sheep hear my voice, and I know them, and they follow me. I give them eternal life, and they will never perish, and no one will snatch them out of my hand. My Father, who has given them to me, is greater than all, and no one is able to snatch them out of the Father’s hand.”
*Philippians 1:6: “And I am sure of this, that he who began a good work in you will bring it to completion at the day of Jesus Christ.”