There are many kinds of knowledge. Most people in this discussion are referring to intellectual knowledge. That can usually be the most trustworthy, however there is a trap in that. It was discussed somewhat in another thread referring to “Confident Ignorance”
There are other forms of knoweledge, for instance, Carnal knowlege.
Then there is spiritual knowledge, as it relates to the major religions.
There is also “knowledge of the heart”, as I believe, Chloe referred to. (notice I used the phrase “I believe”, because I could be wrong.) 
Then there is experiential knowledge, knowledge of self, etc.
The subject of knowledge and belief is the center of the major religions. Faith too. It is a kin to knowledge. In our daily lives, we trust on our knowlege, beliefs and feelings to do even the most simple of tasks. This is all really heavy stuff.