Let me make it simple
Religions didn't say that God created life on earth and earth alone...They simply talked about life on earth...which is the life that concerns you...the living being that is living on earth!! and not on another planet!!
AND THAT'S BECAUSE IT IS ADRESSED TO YOU

THE HUMAN BEING

If there is another life then so be it!!! you will still live by what the morals and codes that you...the human being lived by!!
Mesh 2osset mesh majbour yenzakar bas MA BI2ADDIM W MA BI2AKHIR!!!
So your argument is that IF life existed on another planet and IF they visited and IF their was an inter-species wedding...then religion would be a lie???
tayeb ra7 emshe ma3ak w 2ellak bi kell basata: eza 7abba lal makhlou2a Allah yhannihon

there is nothing wrong with it

because the prophet spread the same message in both planets and there is nothing against that!!
you're not being logical!!
1- Having studied religion in school does not make you an expert in religious matters.
2- Mesh 3ala zaw2ak abadan

if your logic is faulty hay meshkeltak
3- No the concept of our religions does not deny the existence of life outside of earth because there was no such denial...it only speaks of life on earth because that is the life that concerns you the earth-bound human being.
If you want to further this discussion you will need to get me proof from religious books that such denial took place. Ya3ne there will have to be a passage that says in one way or another that life does not exist outside of earth.
And as abousoun explained once.
<=/=>
=/=>
Ceci n'implique pas cela.
Meaning that if the religious books only spoke of life on earth it doesn't mean that life outside of earth does not exist.
Mesh if extra-terrestrial life existed then it should be mentioned on earth...
BECAUSE...and for the last time....these religious teachings are adressed to you

and not to the aliens
And God is talking to you! about stuff that concern you!! What aliens do and how they live or even their mere existence ma 7a y2assir 3lek!!