A loose analogy of religious/spirituality and certainty:
I can know with certainty what an apple tastes like to me because I can go taste one. I can then tell you about it, but, you cannot know with certainty what an apple tastes like unless you go taste an apple.
So you go taste an apple…We each at this point have the certainty that we have tasted apples and we are then telling each other about the taste of apples, I say they are certainly crisp and tart, and you say they are certainly soft and sweet, we disagree but we are both right.
Let’s say we were tasting the exact same apple. One of us might like the taste and the other dislike the taste, neither of us are right or wrong AND we both at that moment hold truth through experience about the apple and even then we still disagree with each other over the experience that we interpret as truth.
But at the core of this analogy (no pun intended) it breaks down because apples are something we can actually put our hands on and objectively experience over and over.
Spirituality is even more subjective than experiencing the taste of an apple…yet we have far less acceptance of different opinions in religious discourse.