I think Paul was highlighting the difference between those who are really sent by the Lord to speak His words in the Spirit versus those who say they are sent by Him but really are not (false apostles = falsely sent).
There was (and still is) a big difference between those who preach the Word of God sincerely in the Spirit of Truth and those who do not (false prophets/false apostles).
That difference is in the display of the power of the Spirit within the heart of the listener.
Paul’s preaching of the testimony of God came with the demonstration (manifestation) of the Spirit and of power. That demonstration of the Spirit and of the power is evident within the heart of the hearer of the testimony of God.
Those who are falsely sent (false apostles who contended with Paul also) do not have this accompanying demonstration of the power of the Spirit within the heart of those they “preach” to.
They must use and rely on persuasive words of human wisdom in order to deceive those who listen to them. Without their fine eloquent speaking in their human wisdom, they have no power. That is all they have: fine-sounding words that really do not carry any heavenly wisdom in them and have no demonstration of the power of God within the heart.
Yet, holy men speak as they are moved by the Holy Spirit….and the evidence that this is a person who is really sent by Him to speak with the Spirit of God is within the very heart of those who hear such a person.
The Light shines within the heart of the listener as the day dawns (the morning star) arises as he or she hears the Word of God spoken with true power. The evidence is within the heart of those who hear.
2 Peter 1:19-21 KJV (19) We have also a more sure word of prophecy; whereunto ye do well that ye take heed, as unto a light that shineth
in a dark place, until the day dawn, and the day star arise in your
hearts: (20) Knowing this first, that no prophecy of the scripture is
of any private interpretation. (21) For the prophecy came not in old
time by the will of man: but holy men of God spake as they were moved
by the Holy Ghost.
Those who are falsely sent (falsely say they are sent of God) do not have this effect within the hearts of others. They must rely on great swelling words of emptiness as they privately interpret the Bible for their own gain.
We receive the witness of men (who speak as they are moved by the Holy Spirit) but the witness of God (WITHIN our very own hearts) is greater.
1 John 5:9-10 KJV (9) If we receive the witness of men, the witness of God is greater: for this is the witness of God which he hath
testified of his Son.
The Light shines within the very heart of the hearer that this is His Son (whom we are to listen to) who speaks.
The Son of God speaks to people via “strangers” sent out by Him to speak His words. He that believes on the Son of God (as they hear His testimony) has the witness of God within himself…within the heart…that this is His Son speaking to the ears.
(10) He that believeth on the Son of God hath the witness in himself: he that believeth not God hath made him a liar; because he
believeth not the record that God gave of his Son.
Falsely-sent speakers (who are sensual and do not have the Spirit) do not have this accompanying witness of God within the hearts of those they speak to.
They must rely on “great swelling words” to deceive people into listening to them. They speak empty words having men’s persons in “admiration” (Greek : thaumazō = “wonders”) because of profit.
Jude 1:16 KJV (16) These are murmurers, complainers, walking after their own lusts; and their mouth speaketh great swelling words, having
men's persons in admiration because of advantage.
That is all false Christs and false prophets have are “wonders” (great swelling words spoken with eloquence which appeal to human wisdom) to deceive those who “wonder” or admire their words.
They also show “great signs”….outward signs of supposed inward (behold, He is in the secret chambers) realities.
There is nothing they do or speak that result in an inward display within the hearts of their listeners of the power of the Spirit. They must rely on outward signs that fascinate the senses of people and speak fine-sounding words in order for people to “wonder” in admiration after them. They do this for their own profit’s sake.
Matthew 24:23-28 KJV (23) Then if any man shall say unto you, Lo, here is Christ, or there; believe it not. (24) For there shall
arise false Christs, and false prophets, and shall shew great signs
and wonders; insomuch that, if it were possible, they shall deceive
the very elect. (25) Behold, I have told you before. (26)
Wherefore if they shall say unto you, Behold, he is in the desert; go
not forth: behold, he is in the secret chambers; believe it not.
No so with the presence (coming) of the Son of man. His presence is very different from those who are “false Christs” and “false prophets”.
Those who hear the Son have the witness within their very hearts as the “lightning” shines out of east (the rising of light within the heart) and shines even unto the west (the darkness where the sun had gone down).
It is very evident in the darkened heart of those who hear
the true voice of the Son as the “morning star” shoots rays of light with our very own hearts making things light. The witness of God is within the once-darkened heart and speaks that this is His Son and we are to listen to Him.
(27) For as the lightning cometh out of the east, and shineth even unto the west; so shall also the coming of the Son of man be.
Thank you for reading and considering.