What will be the largest religion in 2050?
Given the birth rate and youth of the population, it will obviously be Islam.
Time works for them, you might say
It has more to do with the failure of the others. And never forget, Islam hates atheism the most.
You could look at it this way: If you don't return to God by the love of Jesus, you will by the sword of Muhammad.
Christianity had a chance, but has failed. Same as the Jewish. Islam itself may be failing as well, and the time to unite them all is near.
You could also say God is eternal, and even religions may come and go, regardless of what you believe. But to not believe, means you are denying your own existence in a faith of non believing, as you cannot tell where you come and where you are going, which is the reason of all.