Ask your Muslim friends and classmates to explain their difference between Sunni and Shia, and the Wahabi form of Islam. Ask them why their Quaran has so many shiria quotes from our Holy Bible, 700 to over a 2100 years later. (The old and new Testments). Ask them why Mohammed, the last messenger of Allah, is long different from God’s only Son and our Lord and Savior Jesus The Christ who came to die for all our sins. Did Mohammed rise from the dead and ascend into heaven to be sit on the right side of Allah?
That is why we have the Holy Trinity, God the Father, Jesus, God the Son who was sent to die for our sins, and the Risen Jesus, God, the Holy Spirit (because we humans cannot understand God’s ways of bringing part of himself back to him so we refer to him as two different entities, a human, and a spirit in human thinking).
Let’s face it. Our Father is much older in belief than Allah, and is the first to be worshiped by humans as Our Father Which Art In Heaven. Even when Martin Luther placed the 95 theses upon the church door at Worms, they still referred to Our Holy Father.
We used to have our women cover themselves so that only their husband could see their beauty, but that was about a thousand years ago. True, there are religious sects in Christianity that favors a certain form of dress, but that is what they are, sects, not a religion. Even in our own Holy Church our women until recently had to cover their heads before entering. Some ladies still adhere to that tradition. In the Jewish religions this also holds true of certain headdress for men and coverings for ladies. However, it is not a tradition in Islam, it is a law, and if that law is broken, the woman will be stoned to death.
Recently we have seen “honor killings” of female Muslims. Young women killed by their own fathers and brothers because they were "becoming too western"and bringing shame upon the family. How many Christian women have been killed just for that reason in the last 500 years?
The problem is when you try to discuss religious differences with Muslims, it quickly becomes a “Jihad” with them, a form of retaliation because of their current form of Islam, Wahabism, that states anyone who disagrees is an infidel and must be exterminated like the vermin of the earth. Wahabism has a saying: “You may kill me, but then you have to kill my son, then his son, then his son.” Unfortunately that is the revised Islam teaching we are seeing today. The original form of Islam spoke of peace just as our Holy Scriptures. However that original has been ursurped, much like the Inquisition 500 years ago.
). If you imagine an ice cube, it has solid, liquid and gas all at once. All are equally water, but all are distinctly different. At the same time. Sounds like the Trinity to me. 
