As Lawrence Principe points out in his Secrets Of Alchemy, Alchemy was in fact the precursor to our modern notion of 'Chemistry'. The alchemists had theoretical foundations for their work which were inspired by and often incorporated 'unscientific' notions of divinity. At the same time however it's very important to remember that in contemporary terms this wasn't unusual, it's only in hindsight that we can say Newton's mathematical work was more scientific than his theological or alchemical work. (Having read this scholarly book on the subject which spares the bullshit, I quite recommend it.)

To people with the 'Magicians Mindset' as Keynes might put it, the world has a rational soul underlying it which can be teased out by careful study of all things. If you're a Christian and start with this prior belief, then it makes perfect sense that you should expect your theological studies to inform your understanding of the natural world and your understanding of the natural world to inform theological studies. This is a mindset where metaphors and abstract connections are not of the human mind. Rather, they represent features of the territory showing us God's divine authorship of the world.

Another good book that outlines some of this is Hall's The Secret Teachings Of All Ages, which discusses the essentially Aryan (Indo-Iranian) thesis that all theological traditions discuss the same underlying esoteric doctrine which itself descends from one civilization. Having been written in 1928, Hall speculates Atlantis. (Naturally, you should take this text with perhaps more than just a grain of salt.) As far as I know the modern version of this thesis usually places the ultimate originating civilization in India.

https://www.amazon.com/Secrets-Alchemy-Lawrence-M-Principe/d...

https://archive.org/details/The_Secret_Teachings_Of_All_Ages...

For anyone interested in the history of alchemy, I recommend "The Secrets of Alchemy" by Lawrence M. Principe. Great insight into the actual history of the subject without getting caught up in hidden-mystery bs.

https://www.amazon.com/Secrets-Alchemy-Lawrence-M-Principe/d...