“One who prays to dead humans for favors cannot possibly know the Holy Spirit.” Sometimes you go too far. Paul would not have troubled himself to write so many letters to the various groups he evangelized if believers could not fall into error. Besides, if this falling into error were not possible, you and I would have no reason to get on these threads and cajole believers to ‘search the scriptures’.
Are you telling me that you see allowance in the word for prayers to dead humans?
Paul exposed the errors he saw rather well, and it is only his tendency toward very long, complicated sentences of self revelation that I think can confuse some.
Of course there is the problem of those that have not studied the Tanakh, trying to understand his words that are taken therefrom. There is no path to understanding in such a case.