Misconceptions on Hindu Religion-1

The other day I was reading a book on my gurudev, whilst returning from work. Out of curiosity, one of the colleagues sitting next to me, wanted to see that, since we three--the colleague, the book & I--indulge in Bengali language. He was going through the book randomly & was asking me, what is the book about. I said, "Its on my gurudev, mostly reminiscences written by many people, who were deeply influenced by my gurudev's life & teachings." He started asking me about the order & was surprised when I talked about Ramakrishna order, who we consider, an incarnation of the Supreme Being, or as per Swami Vivekananda proclaimed,"avatara-baristhaya", Shri Ramakrishna is the God of all avatars[incarnations].
The colleague being a muslim, was telling me that they believe in a formless God, Allah, and was asking why Hindus believe in God, who has a form?
Well, many people have asked me this question before, so it was easier for me answer this question.I replied, "Well, Hindus actually believe God in both forms--having a definite form & without a form.However, our scattered mind cannot think of the God in His infinite form-thats why, an Idol, a picture or any form, that is symbolic of god. But, through continuous practise of devotion, prayers, as the level of mind elevates, one can pray to God in any form--both in His formless or in form.
"However the basic concept is same--All gods are same-they are different, as per their names, as per their forms. Rigveda proclaims "Ekam sadviprah bahudha vadanti", the one is many, so say learned people. Shri Ramakrishna used to give an example. People of three religions are fetching water from the same pond, from  different banks. Hindus call it, "Jal", Muslims call it, "Paani", Christians call it, "Water/Aqua", but they are fetching the same water, in different names, from different banks. So is religion, Hindus are praying to "Vishnu, Ram" Christians to,"Father, God", whilst Muslims to "Allah".

[I will write more....]