Your little Sham-Wow is easily exposed when we read the verse in context.
1 Corinthians
2:12 Now we have received, not the spirit of the world, but the spirit which is of God; that we might know the things that are freely given to us of God.
2:13 Which things also we speak, not in the words which man's wisdom teacheth, but which the Holy Ghost teacheth; comparing spiritual things with spiritual.
2:14 But the natural man receiveth not the things of the Spirit of God: for they are foolishness unto him: neither can he know [them], because they are spiritually discerned.
2:15 But he that is spiritual judgeth all things, yet he himself is judged of no man.
2:16 For who hath known the mind of the Lord, that he may instruct him? But we have the mind of Christ.
This is simply saying that the Holy Spirit is profitable for the man of God to live and grow by. We get the Holy Spirit after we make our decision, not before.
If I am not mistaken, you are applying the word "WE" in verse 12 to be the natural man, when in actuality, it is referencing those that are sanctified in Christ Jesus, called to be saints, 1 Cor 1:1.
Those verses that have reference to the natural man, before he has been quickened, are verse 11 & 14.
Eph 2:1 indicates that the natural man that is still dead (spiritually) in trespasses and sins, and, therefore, cannot make a spiritual decision, because he cannot discern the things of the Spirit, is quickened to a new spiritual life, and then, and only then, can he began to understand spiritual things as he is taught, and grows thereby.
What you seem to be trying to do, is to make the natural, unspiritual man, be able to make a spiritual decision, in which , ha cannot do until he has been born with the indwelling of the Holy Spirit.
The natural man only has faith in man and what he accomplishes 1 Cor 2:11.
You have been taught, falsely, that mankind has something to do to get delivered eternally, and the scriptures do not teach that.
Most all of God's , well intended, children do not divide the salvation scriptures properly. Save, salvation, saved, according to Greek, means, deliver, deliverance, delivered. We are delivered eternally, and we are delivered from the things of this world, as we sojourn here in this world, by following God's instructions as to how we are to live our lives.
There is a deliverance, eternally, not by our works, and there is a deliverance, here in time, by our good works, which confuses most into believing there is something we must do to get delivered eternally.
Scripture proves scripture, and they must all harmonize to understand the doctrine of Jesus Christ.