According to the dictionary, to know has 6 different contemporary meanings (when used with a direct object): 

1. to perceive or understand as fact or truth; to apprehend clearly and with certainty; e.g. “I have a clear and certain understanding of eternal families.  My dead grandfather came back and said ‘yup’ that’s the way it is.”
2. to have established or fixed in the mind or memory; e.g. “I would be able to pick Jesus out of a line-up.”
3. to be cognizant or aware of; e. g. “I am aware of their being a devil on my shoulder, prodding me to do evil; can you guys see this?”
4. to be acquainted with (a thing, place, person, etc.), as by sight, experience, or report; e.g. “I have met Thomas S. Monson, and he sure looked like a prophet to me.”
5. to understand from experience or attainment (usually fol. by how before an infinitive);  e.g. “I understand the gospel because I have lived it and it makes my life better.” 
6. to be able to distinguish, as one from another;  e.g. “I know this church is the one that Jesus leads vs. those other false ones that Jesus merely dabbled with.”

To believe, on the other hand, has the following 5 meanings (when used with a direct object): 

1. to have confidence or faith in the truth of (a positive assertion, story, etc.);  to give credence to; e.g. “I have confidence in the idea of the atonement and that it will apply to me.”
2. to have confidence in an assertion;  e.g. “I believe that the church is a restoration of the early Christian church.”
3. to have a conviction that (a person or thing) is, has been, or will be engaged in a given action or involved in a given situation;  e.g. “I believe Jesus was resurrected.”
4. to suppose or assume; understand (usually fol. by a noun clause);  e.g. “I believe in the counsel that was given at General Conference.” 
5. to believe in a) to be persuaded of the truth or existence of; b) to have faith in the reliability, honesty, benevolence, etc., of; e.g. “I believe I have heavenly parents who care about me.”

Ether 12:6 - I would show unto the world that ^afaith is things which are ^bhoped for and ^cnot seen; wherefore, dispute not because ye see not, for ye receive no ^dwitness until after the ^etrial of your faith.

Alma 32: 18 & 21 – 18 Now I ask, is this faith? Behold, I say unto you, Nay; for if a man knoweth a thing he hath no cause to ^abelieve, for he knoweth it. 21 And now as I said concerning faith—^afaith is not to have a perfect knowledge of things; therefore if ye have faith ye ^bhope for things which are ^cnot seen, which are true.

What do people at church mean when they say they “know” things they relate in their testimony?  Here are some possibilities:

1. They aren’t certain, but they’ve decided to act on their hope (the first stages of faith).
2. The language of certainty is the norm; they are simply spouting cliches or don’t want to sound “different” by expressing what they believe or hope.
3. They haven’t questioned to this point in their life or experienced doubts; therefore, they are “certain” by default.  They still have the unblinking faith of a child.
4. They have experienced a witness of a specific concept after acting on their faith.  They “know” this specific thing based on that witness.
5. They have experienced some general sort of “witness” (loosely defined) that they are applying holistically to all concepts taught at church, assuming that one witness covers all points of doctrines (all win or lose together).

So, what do you think it means when people say they “know”?  Is it a cliché that is damaging to those who don’t “know” but assume everyone else does?  Is it dishonest?  Is it an act of faith to say we know when we only hope or believe?  Would you rather hear more accurate language in testimonies?

Discuss.