It says it clear as day in that passage that the sow was washed, which is cleansed...................
" and the sow, after washing herself, returns to wallow in the mire.”
If you take this with the rest of the passage it says
they escaped the defilements of the world,which is cleansed of their sins.
They escaped the defilements of the world by being in the fellowship of the church for a time,
where they learned of Jesus Christ and the way of righteousness.
And it says how they escaped, and it was through Jesus Christ,
No, they escaped by
knowledge of Jesus Christ.
Peter's strong language here is for the morally corrupt false teachers of chp 2, who in their apostasy
are leading the new immature Christians (2:18) into corruption and sin.
It says they escaped which is the only way a person can be cleansed of their sins. Then it goes to say they are caught back up in sin, and overtaken by them,
their ending has become worse then their beginning. Because they would have had salvation/eternal life if they would have continued in His ways, but they turned away to go back to a life of sin.
Yes, it is better to be ignorant than to be an apostate, which in effect condemns
the way of righteousness, saying it knows something of that way having been in it for a time,
but has found fault with it, and falsehood in its truth.
At least ignorance does not condemn The Way.
Peter describes the corruption of the false teachers in 2:1-19, and
the apostasy of these false teachers in 2:20-22, comparing them to
dogs that return to their vomit and pigs that go back to wallowing in the mud.
The "washing" of the pig is simply the reference point for "going back,"
as "vomiting" of the dog (not mentioned) is the reference point for "going back,"
and "knowledge" of the Christian life of the apostate is the reference point for "going back."
All apostates have apostasized
from The Way,
and their apostasy is to show, and
does show, they were never saved (1Jn 2:19),
not that they have lost their salvation