You say that as soon as a person repents that he receives the Holy Spirit. I beg to differ with you because in the 8th chapter of the book of Acts they all believed and they were all baptized but no one had the Holy Ghost. Peter and John had to go down and pray for them and then they received the Holy Ghost. It seems that when you say that the scriptures are not understood by those who are natural and unconverted that you are talking about yourself.
Men cannot be saved by water baptism. Men can only be saved by the quickening of the Holy Spirit. John 20 show the Lord Himself breathing on those disciple the Holy Spirit. At Pentecost those same disciples received a filling of the Holy Spirit to do the work the Lord had for them.
Just how did you come to know the Lord? By baptism or by belief? By grace through faith apart from works? Did the Lord draw you by convicting you of your sin, His righteousness and the judgment of God upon sin?
For the cause of Christ
Roger