On what basis can we evaluate whether a person is entirely sanctified or not? If it is on the basis of how good we can be, then one would be on shaky ground.
As I said, it is something that is entirely invisible.
Because even if someone outwardly exhibits behaviour that would denote entire sanctification in his life; there is still the secret life that no one knows about except them and the Lord.
So then, we can only determine whether someone is righteous outwardly; and there are those who do have such a righteousness.
But of course in looking at the lives of such, the person who desires to deny the doctrine can say that there must be some secret sin in their life, and that their outward righteousness only makes them hypocrites; for if they were real people they would wear their heart on their sleeve and everything would be laid bare before the public.
What is not considered is that Jesus told us to clean the inside of the cup and platter so that the outside might be also clean.
So then, there are those who are outwardly righteous before men and do not have the righteousness of faith (an inward righteousness); and there are those who do have that inward righteousness.
But those who do have it do not go around saying, "I have it." Their attitude is that they have room to grow; for that is the attitude of those who are perfect (Philippians 3:12-15).
I believe it bears mentioning that Jesus said that unless your righteousness exceeds that of the scribes and Pharisees, you will in no wise enter in to the kingdom of heaven (Matthew 5:20). Since this is the case, either such a righteousness is possible or else no one is going to enter into the kingdom of heaven.
I think that this is an airtight case for the concept that such a righteousness can be obtained in this life.
The righteousness of the scribes and Pharisees was impeccable according to the law. The only righteousness that might exceed it might be a righteousness that is on the inside and that is in fact also impeccable according to what is on the inside.
In Romans 5:5 we find that the Lord is able to shed abroad His love in our hearts through the Holy Ghost. This love is the fulfilling of the righteousness of the law within us (Romans 8:4, Romans 13:8-10, Galatians 5:14, 1 John 5:3, 2 John 1:6). And it is practical in its nature (1 John 3:17-18).
These things can indeed be seen of men; but those who carry these things in this day may indeed be far and few between.
If even no one today carried this righteousness that I speak of, it would not mean that it is impossible to obtain it and neither would it lessen the fact that this is the righteousness that is required of us by the Lord (see Matthew 7:13-14).