He knows how many hair shafts we have it is impossible not to hear our prays (from Christians or not).
But as Jesus told: why do you call my name and you don't do my will?
I know one thing when He will decide where we belong (with Him or not) none will say it is unfair (Christian or not).
I believe the reason is that as we treat other people this way will be treated by Him.
Hebrews was the chosen nation and the scripts said that all the others was lost.
Jesus when he died went to the deads to teach them for 3 days. Many of them followed him and saved. So in paradise will be some of our anchestors b.c. and many of Hebrews in hell.
Recent Orthodox saint told that in paradise will be people from other religions but it isn't our concern how this will be done. Jesus will decide and will judge fair everyone. This is something I heard but no scripts say so. It was something that was told verbally from a recent Orthodox saint to another Christian, but the Final Judgement isn't our job afterall.