"If there is only One God, then why are there so many religions?

Answer:
Allah does not force anyone to submit to Him. He has layed out a clear path and then made it known to them the two ways (Heaven or Hell). The person is always free to make his or her own choice. There is no complusion in the way of "Islam." Whoever choses to worship Allah without partners and is devoted to Him and is obeying His commands as much as possible, has grasped the firm handhold that will never break. Whoever denies God and chooses some other way to worship or not to believe at all, for them there is an eternal punishment that is most horrible (Hell).

All religions originated with Allah and then people began to add or take away from the teachings so as to take control over each other. Man made religions are an abomination before the Lord and will never be accepted. He will only accept true submission, obedience and in purity and peace to His commandments.