The closer someone is, in reality and not in one’s fantasy, to God, the more they feel unworthy, sinful and more sinful than all people. This is how the Holy Fathers felt; there are many examples of which you yourself know.
The publican felt sinful for another reason. But admitting to his sinfulness he did not justify himself and only asking mercy and forgiveness of the Lord received it. All have an unpayable debt before God. No podvig can pay this debt. The Lord says that if ye shall have done all those things which are commanded you [Luke 17:10] (that is, all the commandments) then consider yourself an indecent servant who must do everything that their master says. So all of us, constantly breaking the commandments, must have the state of soul like the publican. Don’t look for any kind of merits in yourself whatever types of podvig you have carried out. We are permanently unprofitable servants. Only the mercy of God forgives the repentant and includes them in the Kingdom of God.
This is why the seeking of hightened spiritual states is forbidden by the Lord and the Holy Fathers. All of our inner podvig needs to be concentrated on repentance and everything that assists in that repentance. And God’s grace will come itself when the place is clean and if the Lord wishes. If the struggler does not have a sincere, heart-felt feeling of sinfulness and a contrite heart then they are in delusion. The struggler of prayer especially has to have the prayer of the publican and a contrite heart or, otherwise, they will be deceived by demons, get a high opinion of themselves, and become vain and deluded. From this may the Lord save us.
Here is an answer for your desire to know what it means to have the constitution of the publican. The Lord’s parable about the publican and pharisee showed both how we need to pray and with what constitution and how we need not to pray (as the pharisee). After the Lord’s advent and his suffering the Holy Fathers substituted the prayer of the publican with the Jesus prayer. The meaning is the very same.
February 18, 1954