Even though it's logical there is nothing in the Bible that expressly states that spirits have souls, but that's what we're going to dig down to and it's a meaning which we can bring out of the text.
Spirits and Gravity
Biblical Exposition
We're not building a doctrine upon one verse of scripture. The doctrine has already been built, with an extensively documented process of deductive logic. What we're doing is using our doctrine to understand a passage.
O Lord, Search my Kidneys
It may seen random or coincidental that the two meanings of the word reins: a bridle for a horse; or the kidneys, can be both be part of a physiological process which can guide and influence us.
O Lord, Try my Kidneys
If the Lord can try our hearts to find out, or really show us, whether our motivations are pure or not, then this applies to the kidneys which regulate the blood that can potentially influence the heart.
Kidneys are Reins on our Heart
The Hebrew word sometimes translated as reins is elsewhere translated as kidneys. This is another usage of the word in modern language, and it's the origin of the word renal.
The Nations Shall Gather at Jerusalem
During the tribulation the Lord will establish Jerusalem as the summit of the mountain of the Lord and all nations will flow to her. The Earth will be full of the knowledge of the Lord like the waters cover the sea.
Imagine Peace
Our other god, SciPop, says don't believe in God, don't go to church, be at peace, nothing bad is going to happen to you. Become an alcoholic, a drug addict, and commit suicide. You'll be fine.
Walking After Other gods
We have a predicament: Souls are eternal but our bodies will eventually die, however, we have no "science" to tell us what happens to our soul after our body dies.
Walking in Imagination
If it's plausible it's possible. If it's possible it happened. It has to have happened because we exist. The chances of us existing are so remotely tiny that our existence proves our hypothesis (whatever it is).
Their Thoughts Were Evil
The universe was created as a way to purify all of the corruption out of the world, and this is being brought about through the action of gravity. No one wants you to know this. Why? Because their thoughts are evil.