Liked this definition of faith from Nigel Turner, a Greek Scholar, and, according to the book jacket, a contributor of two volumes to J. H. Moulton’s, Grammar of New Testament Greek, and author of articles in the Interpreter’s Dictionary of the Bible, Hasting’s Dictionary of the Bible and Manson’s Companion to the Bible. Turner also worked translating the British and Foreign Bible Society’s, Translator’s New Testament.
Speaking about the meaning of faith in his book Christian Words, pg. 157
“ …faith is a state of mind transcending ordinary knowledge, a conviction with a firmer basis than sense or reason, confidence in what God says without further evidence, ‘the basis of what is hoped for, the evidence of things not seen’ (Heb 11:1)
"It should be noticed that in many ways the verbs pisteuo and ginosko (to have divine insight) in St. John’s gospel are synonymous, although Jesus Who is said to ‘know’ God is never said to ‘believe in Him. However, to ‘believe (11:42) and to ‘know’ (17:3) are used in the same context. Clearly the words are synonymous in a passage like this: ‘they have known… that I came out from Thee and they have believed that Thou didst send Me’ (17:8). Faith is deep insight, sure and divine knowledge.”
This was the bit that helped assure me I wasn't on the wrong track when, after meditating on Mark 11:23 for several months, I realized that, in the Bible, faith/believing means to know in your heart, to perceive in your spirit, to see with the eyes of your heart, to hear with the ears of your heart.
This is the faith it takes to move mountains, you must first know in your heart that the particular thing you're saying will come to pass. Until you know that you haven't begun in faith.