The spiritual things referred to in 1 Cor 2:14 relate to that which Paul spoke among them that are perfect (perfect as in they were "spiritually mature" ... not perfect as in they "do not sin").
1 Corinthians 2:
6 Howbeit we speak wisdom among them that are perfect: yet not the wisdom of this world, nor of the princes of this world, that come to nought:
7 But we speak the wisdom of God in a mystery, even the hidden wisdom, which God ordained before the world unto our glory
Please note that in 1 Cor 2:1-2, Paul indicates he came not with excellency of speech or of wisdom and that he could go no further with them than Jesus Christ and Him crucified.
Not because he didn't want to speak the wisdom of God in a mystery, even the hidden wisdom, which God ordained before the world unto our glory.
But because the church at Corinth was not spiritually mature. They were still in spiritual infancy because they had left off following Christ and had broken off into factions wherein some followed Paul or Apollos, or Cephas:
1 Corinthians 1:
11 For it hath been declared unto me of you, my brethren, by them which are of the house of Chloe, that there are contentions among you.
12 Now this I say, that every one of you saith, I am of Paul; and I of Apollos; and I of Cephas; and I of Christ.
13 Is Christ divided? was Paul crucified for you? or were ye baptized in the name of Paul?
And this fact is further corroborated in 1 Cor 3:
1 Corinthians 3:
1 And I, brethren, could not speak unto you as unto spiritual, but as unto carnal, even as unto babes in Christ.
2 I have fed you with milk, and not with meat: for hitherto ye were not able to bear it, neither yet now are ye able.
3 For ye are yet carnal: for whereas there is among you envying, and strife, and divisions, are ye not carnal, and walk as men?
4 For while one saith, I am of Paul; and another, I am of Apollos; are ye not carnal?
You need to quit throwing up 1 Cor 2:14 as your standard for supporting a doctrine which is not contained in Scripture.
It is clear from Rom 1:18-20 that some reject that which has been revealed to them, not because God does not want them to believe but because they, of their own volition, reject ... even though the eternal power of God is revealed to them. That is why they are without excuse.
They reject, not because they are not part of some so-called "elect" club you continue to insist upon. They reject because they suppress the truth in unrighteousness. That is why they are without excuse.