Where is the Humility in Mormonism and Seeking after Truth?

"He that trusts his own heart is a fool" (Prov. 28.26). The Bible is constantly talking about the corruptness of men's hearts. And so it is in creating Mormonism and following it.

Truth in Mormonism is gaining an emotional assurance that the Book of Mormon and changes Smith makes to the Bible as being true. This is said to be evidence of the Holy Ghost, and is often referred to as burning in the bosom or spiritual witness or testimony. Where is the humility and honesty in that?

Can't the evil spirit produce a burning in your bosom and impact your feelings to manipulate them based on selfish lies? Doesn't Satan counterfeit God as an angel of light?

https://www.youtube.com/watch?v=j8ESHqWnE4E