The intention of interpreting the Bible spiritually is to explain seeming contradictions in the Bible as well as interpret it as the Bible itself says it should be understood.
1Corinthians 8:1-4 “Now as touching things offered unto idols, we know that we all have knowledge. Knowledge puffeth up, but charity edifieth. And if any man think that he knoweth anything, he knoweth nothing yet as he ought to know. But if any man love God, the same is known of him. As concerning therefore the eating of those things that are offered in sacrifice unto idols, we know that an idol is nothing in the world, and that there is none other God but one.”
To understand 1Corinthians 8:1-4 and the "knowledge" that is being spoken of here, we need to know what the idol, that is nothing in the world, represents. An idol is an image or tangible representation of something rather intangible. An idol or image represents physically what is spiritual or indescribable. An idol is only a representation and is nothing in itself. The verse is saying that knowledge or understanding which is gained according to the tangible representations (idols) is not the same as the knowledge or understanding that is gained from God.
With respect to knowledge as it relates to the tangible (idol), someone may have this knowledge, and in so doing, think they understand something solely and completely by the physical representation (idol). However, according to 1 Corinthians 8, they know nothing as they should know. Therefore, the physical representation represents more than what simply meets the eye.
The "eating" spoken of in verse four should be understood figuratively as in food for the soul. When we take in (eat) knowledge gained from the physical representation, we need to realize the tangible or carnal understanding is nothing in itself. So we then must go on and seek for the actuality which the idol simply represents. The idol or physical represents something that is actually intangible or unknowable.
If the knowledge of something brings with it a sense of pride rather than charity (compassion, goodwill, love and forgiveness of others), 1 Corinthians 8 tells us to take that knowledge and consider that we don't really understand it as we should. Humility with charity can bring us beyond the carnal understanding and on to the spiritual meaning that the physical representation symbolizes.
Isaiah 28:12-13 “...yet they would not hear. But the word of the LORD was unto them precept upon precept, precept upon precept; line upon line, line upon line; here a little, and there a little; that they might go, and fall backward, and be broken, and snared, and taken.”
Isaiah 28 says that the word of the LORD is will snare (entice away from the truth) those that do not hear God. Isaiah says that there will be those that understand and those that do not.
1Peter1:12 Unto whom it was revealed, that not unto themselves, but unto us they did minister the things, which are now reported unto you by them that have preached the gospel unto you with the Holy Ghost sent down from heaven; which things the angels desire to look into.
2Peter1:20-21 Knowing this first, that no prophecy of the scripture is of any private interpretation. 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.
1&2 Peter says that prophecy of the scriptures is revealed and interpreted to us by the Holy Ghost. The Holy Ghost, or Holy Spirit, is a spirit of "truth" to be acquired within us. One reason there are great debates concerning Bible interpretation, even to the point where people believe it is false, is explained by what is said in 2Peter 1:21 and Isaiah 28:13. We must ask ourselves if the interpretation we are thinking to be true is sincerely Holy Spirit inspired. We must search out our interpretation to be sure that it is the truth. We must compare teachings with other scriptures to be sure there is no contradiction. The interpretation should encourage a sense of charity rather than a lifting up with pride. The word of the Lord can cause people to fall backward and be broken and snared, if their minds are not yet opened to the scriptures by the use of this holy sacred "spirit" of truth.
Hebrews 4:10-12 For he that is entered into his rest, he also hath ceased from his own works, as God did from his. Let us labour therefore to enter into that rest, lest any man fall after the same example of unbelief. For the word of God is quick, and powerful, and sharper than any twoedged sword, piercing even to the dividing asunder of soul and spirit, and of the joints and marrow, and is a discerner of the thoughts and intents of the heart.
Isaiah 28:11-13 For with stammering lips and another tongue will he speak to this people. To whom he said, This is the rest wherewith ye may cause the weary to rest; and this is the refreshing: yet they would not hear. But the word of the LORD was unto them precept upon precept, precept upon precept; line upon line, line upon line; here a little, and there a little; that they might go, and fall backward, and be broken, and snared, and taken.
Hebrews 4 and Isaiah 28 above have similar messages. Hebrews tells us to make an effort to enter into rest and cease from our own works lest we fall. Isaiah also talks about the rest of God and how those that would not hear about the rest, would fall and be snared and taken by the word. It says we are to diligently work towards that rest lest we become lost in our own works and not truly hear God. Hebrews says the word of God can pierce us, which can be compared to the warning in Isaiah that says God will speak to those who would not hear of the rest with stammering lips and another tongue. If we are not truly "hearing" what the word is saying we will fall by that same word and it will snare us rather than help us. This seems to be a warning that comes with the use of the word. It can be a detriment if we fail to seek entrance into God's rest and do not cease from what we think we need to do. The word can show us the intentions of our heart and whether they are truly driven by the Holy Spirit of truth.
John 14:17 The spirit of truth, whom the world cannot receive because it seeth him not neither knoweth him: but ye know him; for he dwelleth with you and shall be in you.
Looking at Hebrews 4:10-12 above a little closer, the word twoedged, describing the word of God in Hebrews 4 above means “double mouthed” from Strong’s concordance. This tells us that the word of God is double mouthed. The words of a double mouth can be interpreted two ways. One is understood in spirit and truth, the other is understood carnally, as a mind not seeking rest from our own ideals. One way will bring spiritual life; the other way can bring spiritual death. The word of God is so powerful and sharp that it can divide our soul from our spirit. And that is what we need if our spirit is not one of love and truth. If we allow the Spirit of truth (i.e. Holy Spirit) to help us interpret the scriptures, the life and truth of it will pierce through us until we see the spirit we have. We can then see the true thoughts and intentions of our heart. We are exposed. If our intentions are not one of truth, then that spirit is seen, understood, and separated from our soul via the word. Our soul can then be combined with the Spirit of love and truth.
Now to further explain Hebrews 4:12 and demonstrate how the Holy Ghost can bring a different more deep meaning to the scriptures, the word of God will also divide or differentiate our joint from our marrow. When reading this scripture we need to look at our body as simply a figure or symbol of our true life. Bones give our physical bodies form and structure. Bones protect us and define our bodies. The joint of the bone allows our bodies to move about and be flexible. The joints are essential to our movement, and our movements are what give our bodies an appearance of physical life. Even our jaw has a joint that allows us to breath, talk, and eat. The marrow of the bone, however, has a different function. Blood cells are made in the marrow of the bone. Blood is what gives our bodies life from within. The blood performs all the functions of life that we can't necessarily see with our physical eyes. So when looking at the body as an figure or example of life, we see that the joints represent our external physical life and our marrow represents what truly gives us life from within. Therefore, the word of God will can separate these two live giving forces or show us how to differentiate between these two life forces. The latter will be accomplished if a Spirit of truth is involved in the understanding of the scripture. This Spirit shows us how the word of God will "divide asunder" the joints and marrow (life producing substances) in the spiritual sense.