That's what every jihadist says as well. The Jews are just as certain that Christains are wrong as the Christains are certain the Mormons are.
if one is familiar with scripture it's not difficult to determine....
Every religious sect or cult has its own "scripture" and its own "official truth" based on them. Generally speaking if one is familiar with scripture it's not difficult to determine....though sometimes it takes time to. Anything which opposes scripture should be a red flag
Yes, there are many religions claiming their own truth is “THE” truth...and believe they have it. So someones wrong...they cannot all be right..... Thus people do search to discover where the truth truly is. (I don’t include Islam in that as they do not have that option.)
It is difficult for those who are not Christian to understand as much as it is for Christians to explain why they have determined Christianity answers it all.
But in Christianity ‘we have Christ within us’....not out there somewhere beyond the blue. And that’s the major difference between Christianity and other religions.
Muhammed is dead....Joseph Smith is dead....etc. etc. We have a risen savior. ..... All which He said He would do He did....all which He says He is HE is.....and all which He says He will do you can, with certainty, know that He will do in the future.
It really is quite simple when you get right down to an encounter with Christ...and when it is each individuals time...they know it.