I am studying in a non Muslim college . Is it obligatory upon me to give Dawah to my non Muslim classmates ? And in the Quran Allah عز وجل says " And We never punish until We have sent a Messenger (to give warning) " [ 17 : 15 ] . Does this mean that Allah عز وجل will not punish anyone until the proof of Islam is clarified to them ? Here in India , many non Muslims are living , does this verse apply to them ?