How can we understand spiritual things in the Bible? 1 Corintihians 1-2

1 Corinthians 2:12-15 (NASV)

Now we have received, not the spirit of the world, but the Spirit who is from God, so that we may know the things freely given to us by God, which things we also speak, not in words taught by human wisdom, but in those taught by the Spirit, combining spiritual thoughts with spiritual words.

 But a natural man does not accept the things of the Spirit of God, for they are foolishness to him; and he cannot understand them, because they are spiritually appraised. But he who is spiritual appraises all things, yet he himself is appraised by no one.

1 Corinthians 2:12-15 (NIV)

We have not received the spirit of the world but the Spirit who is from God, that we may understand what God has freely given us. This is what we speak, not in words taught us by human wisdom but in words taught by the Spirit, expressing spiritual truths in spiritual words. The man without the Spirit does not accept the things that come from the Spirit of God, for they are foolishness to him, and he cannot understand them, because they are spiritually discerned. The spiritual man makes judgments about all things, but he himself is not subject to any man’s judgment:

I don't understand cars.  In fact, I don't understand most things mechanical or engineered.   If I came across an engineer I am sure he/she could try to explain to me the aspects of combustible engines and the thrust of energy, etc.   But, without that person in my life I am forced to drop my automobile off at the garage and simply say, "Its going bang-bang on the left side."    I need someone to explain it to me.   So, too, spiritually, Paul says.  In the above passage we see the need for the Spirit of God to explain the Word of God and to produce in us Spiritual knowledge.   We are not capable of understanding or interpreting or discerning spiritual things without the combination of the Spirit of God and the Word of God.   Far too many times the believer leaves it up to a commentary or preacher to explain all things spiritual to them.   There is, of course, nothing wrong with either.  However, it is the pace and dependance with that approach that diminishes what Paul is telling us.   We have, dwelling within us, the very author of the Scriptures.    By comparing God's Word with God's Word we can and should come to an understanding of Spiritual things ... see above: "appraises all things."   The problem with our dependance on others is that we are spiritually lazy.  I don't know mechanical things because I don't care to know them.  I don't study them.  I am reliant upon others not out of need but out of ignorance ... willful ignorance.   In the aspect of Spiritual things Paul tells the church at Corinthian, don't be ignorant.   You have all that you need to be spiritual giants.   You just have to, in faith, execute the process.