The proof is that this is a spiritual battle in the invisible realm is that billions of Muslims hate and want to kill a few million Jews when the Jews have in reality done nothing to them - other than humiliate them in defeating them when they jointly attack Israel.
Of course, the ultimate sin against a Muslim is to humiliate them.
The proof that it is a spiritual battle is that almost the whole world sides with the Muslims against the Jews! When the Jews are like a flea on an elephant’s back......
Another proof is that the whole world is blind to the true picture and believes Israel has so grievously “sinned” that it must be crushed. Even though the proposition is wholly illogical.
Originally, I believe many of the Jews refused to convert, so after battle with Mohammad’s and his disciples the captives were asked again, those refusing were killed - Mohammad personally beheaded 400. However, the highest state any muslim male can attain to to follow in Mohammad’s footsteps - killing Jews. Killing all Jews will deprive future Muslim, should there be any, from this vital action.
Modern Jews in Israel - those that are not suicidal in their love for muslims - have humiliated muslims, but that is just small potatoes compared to the ‘religious’ calling of killing Jews. Christians, Hindus, and assorted pagans - as well as the fellows down the road with the heretic imam or muslims in any other sect.