'Ekam Sad Vipra bahuda vadanti' - One alone exists, Sages call it by various names

In a suburb area of Dehradun, a hindu priest lives in the muslim area and shares a cordial relationship with the muslims. I was once told by my cousin sister, ' you have punjabi blood in your veins'; to which I paused for a while and replied, ' no didi I have B+ in my veins - you know if I am in need of blood, anybody in any part of the world with the same blood group can help me out'. Are we not human beings first and then Hindus, Muslims, Christians, etc.?