350 BCE, Aristotle discovered logical syllogism.
1854, George Boole published "An Investigation of the Laws of Thought" and started Boolean propositional logic.
1879, Gottlob Frege laid the groundwork for First-Order Logic. FOL underpins all modern science and mathematics.
1559, John Calvin finalized and published his
Institutes. At best, in terms of logical reasoning, he could only analyze the scriptures using Aristotelian logic and contemporary scholastic rhetoric, which lacked the formal precision endowed in FOL. His systematic theology lacked the rigor and precision afforded by the modern axiomatic argumentation system. People often conflate logic and rhetoric.
E.g., Institutes, Book II, Chapter 1, Section 8:
Calvin did not use "therefore" in the first-order logical sense. The words "therefore" and "seems" do not go together in their FOL senses. The word "seem" carries subjective evaluation. FOL's "therefore" carries objective precision. He did not think according to the precise syntax of FOL. No one did in the 16th century.
An example of such Calvinism logical flaw is
double predestination. Try to prove that double predestination is true strictly by FOL and you will see.
Similarly, since the time of Frege, many theologians have not been trained in FOL. They suffer the same handicap. Aristotelian syllogism is a primitive precursor of FOL. (See appendix below.) There is now a more articulate and comprehensive logical system.
John Calvin used Aristotle's logical system, which was okay. I prefer the more up-to-date First-Order Logical system when I argue. Simpler logical systems are fine when I am not engaging in argumentation.
See also
Appendix: Reformulate a syllogism into FOL
All humans are mortal.
Socrates is a human.
Using Aristotelian syllogism, we can draw the following conclusion:
Socrates is mortal.