What was the Prophet Muhammad (saw) teaching us when he said, "If the people of the Scripture greet you, then you should say (in reply), 'Wa'alaikum (And on you).' ?"
 Narrated Anas bin Malik:                     the Prophet said, "If the people of the Scripture greet you, then you should say (in reply), 'Wa'alaikum (And on you).' "