In Need of Rhetorics

Paul claimed that he did not use words of wisdom to preach the mystery of God.
When I came to you, brethren, I did not come proclaiming to you the testimony of God (τὸ μυστήριον τοῦ θεοῦ ) in lofty words or wisdom (1 Corinthians 2:1).
He gave the following reason:
that your faith might not rest in the wisdom of men but in the power of God (1 Corinthians 2:5).
Paul did not want to persuade people to believe in God through sophistry. He did not want God's truth to be overshadowed by human cleverness.
But did Paul not use words of wisdom? I'm afraid he did. He was a very well trained Pharisee under the famous Rabbi Gameliel. The epistles he wrote show a lot of Jewish exegesis. Moreover, his rhetorics are very persuasive. He put the skills he had learned in good use for the preaching of the good news. Verses 1 and 5 are his rhetorics only.
Later on, he admitted that he did use words of wisdom on spiritually more mature people.
Yet among the mature we do impart wisdom, although it is not a wisdom of this age or of the rulers of this age, who are doomed to pass away (1 Corinthians 2:6).
It was a different kind of wisdom, though. To support his argument, he quoted again from the Old Testament.
Most of the Christians in Corinth were Gentiles. They did not have any background knowledge of the Old Testament. So, why did Paul quote, at least one piece of text in each chapter? What aim did he try to achieve in doing so? Before we attempt any serious hypothesis, let's look at the raw data.
ἃ ὀφθαλμὸς οὐκ εἶδεν καὶ οὖς οὐκ ἤκουσεν καὶ ἐπὶ καρδίαν ἀνθρώπου οὐκ ἀνέβη, ἃ ἡτοίμασεν ὁ θεὸς τοῖς ἀγαπῶσιν αὐτόν.
What no eye has seen, nor ear heard,nor the heart of man conceived, what God has prepared for those who love him, (1 Corinthians 2:9)
Here, Paul did not quote directly from the Septuagint. He summarized and translated the passage all by himself. A quotation from Isaiah which tells.
ἀπὸ τοῦ αἰῶνος οὐκ ἠκούσαμεν οὐδὲ οἱ ὀφθαλμοὶ ἡμῶν εἶδον θεὸν πλὴν σοῦ καὶ τὰ ἔργα σου, ἃ ποιήσεις τοῖς ὑπομένουσιν ἔλεον.
From of old no one has heard or perceived by the ear, no eye has seen a God besides thee, who works for those who wait for him. (Is 64:3).
Here, the differences are big. Not only did Paul summarize, he even changed ("works for" to "prepared for"; "wait for" to "love") and "smuggled in" some other components: "nor the heart of man conceived" to drive home his own argument. No one had heard of, nor had born witness to the hidden mystery he preached. So, Paul made up this quotation to support his arguments. I wonder how the Corinthians would react to his extensive quotations.
Paul's argument needed back up. What were these? Miracles, the power of the Holy Spirit. Of course, for contemporaries, the actions spoke for themselves. There was no need for Paul to be eloquent. However, with the passage of time, people have lost touch with those miracles. To make them accept your message, you need to be verbally persuasive. That is why Paul had no choice but to rely on rhetorics to get his message through. Persuasive speech is relevant to subjects of all kinds.

My dear Advocate, I think Mongoloids are not stupid. They provide us with a chance to put our preaching into practice. We may not have the rhetorics of Paul we need Your power, Your power to move us to work miracles so that people accept Your mystery, not through our eloquence, but our charity. Amen.