FALSE CHRISTIANS
It has happened to them according to the true proverb, "A Dog returns to its own vomit" and, "a sow, after washing, returns to wallowing in the mire." (2nd Peter 2:22)
Certainly Peter, the writer of this letter, understood what it was like to fall from grace. He had done so on more than one occasion. However, he had learned the difference between those who earnestly made mistakes, and those who deliberately deceived others regarding their profession of Faith. False teachers were to be avoided. They were individuals who never were who they represented to be. As a result, it was always just a matter of time before they returned to doing what they had been doing in the world (as unbelievers).
In the passage above, Peter speaks of a dog and a pig in the same way that we would speak of an unbeliever. The dog and the pig can be scrubbed clean with soap and water, but they are still a dog and a pig. They will continue to do what dogs and pigs do. People who say that they are Christians, but really are not, will ultimately continue to do those things that unbelievers do. They may talk as though they are Christians; but their actions say something else.
We should always seek to know the truth regarding the Word of God. We should evaluate what we hear and what we see. From time to time, we will determine that someone who says that he/she is a Christian, is not acting like a Christian, or teaching the true Gospel of Jesus Christ. Ultimately, they will return to who they really are. After all, a dog and a pig that are washed, are still a dog and a pig!