Paul states in Romans 10:17 that faith comes by hearing, and that is true, but after we hear there must be a thought. Something that takes what we hear and translates it for our heart, so to speak. So faith comes by evidence or at least that is the end game.
If all we ever did was hear something to make us believe it, then we would believe everything we hear. Our thoughts discern what we hear and then we decide what we will or will not believe. And our thoughts have everything to do with our heart, our spirit being transformed from that of a weakened, insignificant creation that is unable to come against even the smallest attack of our enemy into a mighty warrior who will stand his ground any time through any temptation or trial or subversion that comes against us, for we will have been made, or at least will be on our way to being made into a tool of the Holy Spirit used by God to wage war against the legions of darkness. You may not think of yourself as a tool of the Holy Spirit, in fact you may just think of yourself as a tool, but God’s desire for you is to be of use in the spiritual warfare that is constantly engaged by those in the heavenly realms.