Do you know of any concrete way to tie down the accurate usage of the word Faith in the scriptures, and how it might contrast with how people use the word today? Recently the best that I came across was a 13th & 14th century AD English definition. I mostly find that the word today is used to mean an absence of evidence, but something is off about that meaning because we have Biblical characters who are credited with having legendary amounts of faith yet they had way more proof of God than any of us do today.
And it is also sometimes said by a person “A deeper study of scripture strengthened my faith.” More knowledge increased the person’s faith. Well that wouldn’t make sense if faith means absence of evidence, in that case it would make more sense if someone were to say “My memory really sucks and I forgot my reasons for believing in God, but since I still believe in God it means that my faith is much stronger now.” And Faith meaning absence of evidence wouldn’t make sense in science & engineering either since the most knowledgeable person who designed a sturdy bridge would have the most faith in it because her knowledge of its sturdiness was the greatest! The different ways that the word is used are contradictory.
Edit -
On second thought there could be no contradiction if I let Faith in all circumstances mean “It has my full confidence.” So that person A can say “It has my full confidence because I know so much about it” and person B can say “It has my full confidence even though I know almost nothing about it” and both would be using the word properly. However if that’s true then the word Faith would become too ambiguous to use as a critique against someone’s believing in something.
The English word 'faith' is one of those words that descend from the Church concept, but has changed quite a bit - akin to the word religion in a way, which originally referred to being bound to Orders.
You should not look to English prescriptive definitions, but to the concept and usage it is supposed to represent. This is the concept of Christian Faith, which translates the Greek Pistes of the NT. This is a very different animal indeed. For Greek Pistis does mean 'faith', or trust, or what is reliable. It has been translated as guarantee. It is essentially a surety.
Pistes is related to the principle of the Logos, or the innervating principle of the Cosmos (or in Christian terms, God the Son in the manner how God acts in creation or how God is 'knowable' or incarnated therein). Logos is where we get logical from, meaning there is Reason to it. In a greater sense, Pistes, or more notably in Roman Fides, it has a sense obligation, or staying true - hence English Fidelity. So we could have faith in the sun rising, as the gods or the logos had set its course.
In fact, pistis was often used to describe something you were convinced of, that you hold to be true therefore, and in that way it entered the realm of the epistemological. Based thereon, it came to be this modern form which means both what you accept as axiomatically true, as well as often what argument you think is stronger - and also disparaged, as if held in spite of evidence. It was also a mechanism of oratory, to convince.
The latter is not a good fit for the Christian concept though. CS Lewis called Faith the art of holding on to what you believe in spite of changing moods. It is related to your reasoning faculty, as a conduit whereby your reason controls your passions. Thomas Merton said that you only reach faith through reason, and then faith takes over, but you must first struggle there. In Dante, Virgil represents human Reason leading Dante to Beatrice/Grace - he cannot enter paradise, does not become Faith as well, but hands over at its gates. Faith is a surety, a guarantee in Jesus to those who embody Him; it is becoming a Christ, allowing the Logos to work through you, to control the passions or spirit in line with the Reason/Will. It still has that sense of obligation, of keeping the Faith in spite of the attempts of the World.
Christian Faith is assent to, or acceptance of, Christ. Faith in Jesus means to trust in Him. The concept is only very loosely connected to the quotidian usage of the term, I feel. It can mean that you were sufficiently convinced, or it can be axiomatically taken 'on faith', but that is a circumferential idea around it that gets confused with the concept itself. You must acquiesce to follow Jesus and then keep faith, both an obligation on you and a guarantee or promise from God, but the primary sense here is certainly not an epistemological one - except perhaps in Jesus as the way, the Truth, and the life.