Mary & The pagan goddess Ishtar

What is the answer to a friend who says we are worshiping the Babylonian goddess Ishtar when we honor Mary? He uses Jeremiah 44 as proof because we call Mary the Queen of Heaven.

Answer

The fact that a pagan deity was known as the queen of heaven doesn't mean this term can't rightfully be applied, in another sense altogether, to Mary. The pagan king of Babylon, Nebuchadnezzar, is called the king of kings by Daniel (Dn 2:37), yet this doesn't preclude Jesus from being called by the same title (Rv 17:14; 19:16). 

Since the destiny of all Christians is to reign as kings and queens with Christ in heaven (Eph 2:12; Rv 1:6; 5:10), and since Mary is the preeminent Christian, there's nothing wrong with giving her the title which Christ, the King of Kings, bestowed upon her in making Mary his mother.