“Like Marx who hated capitalism but regarded it as a higher form of economic and political organization and welcomed capitalists as sappers and miners of Communism, Christianity detested Islam but honored it for destroying idolatry.”
“Though Christianity has a poor opinion of Islam, yet it regards it as a partner up to a point; it welcomes Islam's role as a cleanser of the "world from the gross pollution of idolatry,”—the name by which the two religions remember all other religions, past or present. This sympathy arises from the fact that the two religions in spite of the long history of conflicts share a common perspective and common ideological premises.”
~ these two quotations are from Ram Swarup’s book Hindu View of Christianity and Islam.
Ram Swarup is right. Political battle between Christianity and Islam has been raging for almost 1200 years, but at a doctrinal level, there is affinity between the two religions. Both are anti-idolatry; both are anti-polytheism. Since Hinduism is the world’s oldest and most widespread movement of polytheism and idolatry, it is the supreme target for both Christianity and Islam.
In my opinion (this is not Ram Swarup’s view), Christianity is a philosopher’s and trader’s religion, while Islam is a warrior’s and tyrant’s religion. In the last 500 years, the Christians have tried to convert the Hindus by coming up with theological arguments and by offering financial incentives. In the last 1300 years, Islam has adopted coercive and militaristic methods for converting the Hindus.