This is your problem. You take a vague, trite phrase like "deeper understanding", drop it in as a main component of your point and then promptly disclaim any responsibility for the use or indeed the meaning of the phrase.
I don't have any problems
I deliberately put it in inverted commas and was responding to NativityInBlack, who used the phrase.
It's a broad concept with the specifics likely varying by religion and tradition, and by individual experience. It's the basic idea that through spiritual and/or religious practice, a different sense of reality can be experienced, maybe a connection with God, and/or insights can reveal themselves. If you're interested in more detail, there is no shortage of texts that can describe and explain it much better than I can.
The 'truth' or otherwise of these is not the point here, hence the disclaimer, it's that there has been many people who claim these things happen. It's a component of many religions, which is the relevance here.