Thank you for contacting Ask About Islam with your question.
Congratulations on your engagement, and I wish you many years of happiness in your up-coming marriage!
A Muslim man is allowed to marry a Christian or a Jewish woman, so if you are already Christian or a Jew, you don’t have to become a Muslim to marry him.
But I hope that you will be convinced that Islam is the Truth and accept it for its own sake, not just for the sake of marrying.
You should know that Muslims believe in One God—Allah in Arabic—Who is the Creator and Sustainer of the universe, everything in it and the whole existence.
God is infinite; that is, He always existed and always will. He is totally unlike any of His creatures and transcends space and time. He knows everything past, present, and future. Nothing can happen except by His will.
God created mankind with innocence and an innate knowledge of Him called fitrah, and with free will to choose between right and wrong.
This life is only a test for us. Someday this world will end and God will resurrect us all and judge us. God is All-Just and also All-Merciful.
He will forgive those whom He chooses to forgive and will punish those whom He chooses. He has told us that the one sin He will not forgive—if someone dies without repenting for it—is associating partners with Him, i.e., worshiping anyone or anything other than Him.
If you look at the world around you and contemplate, you will realize that someone must have created it. It could not have just fallen together in such order and perfection as we see around us; and where would the pieces have come from?
And when you see that many good people suffer while many bad people enjoy an easy life, you must wonder what the purpose of life is if there is little justice. Muslims believe that justice will come in the next life on Judgment Day.
God sent prophets and messengers to mankind to set good examples for people and to teach them to worship God alone. These prophets and messengers were completely human, and Muslims do not worship or pray to them.
The last of them, and the final one, was Prophet Muhammad.
The Quran was revealed to Muhammad (peace and blessings be upon him); it is preserved exactly as it was revealed by the Angel Gabriel in the Arabic language. However, there are many translations of its meaning available in most languages.
In addition, Muslims believe in the Angels, in the Divine Decree and the Books that were revealed to some of the prophets, but only the Quran remains uncorrupted.
As for their acts of worship, Muslims must perform ritual prayers five times a day. They must pay a small portion of their excess wealth each year to help the needy or for other causes stated in the Quran.
This payment is called zakah. They must fast during the month of Ramadan, and if possible, they must make a pilgrimage (Hajj) to Makkah once in their life.
But Islam is not just made up of beliefs and ritual acts. Muslims are commanded to enjoin good and forbid wrong.
Muslims should strive to make their families, societies, countries, and the whole world better places for everyone. And every deed a Muslim does in obedience to God is an act of worship.
A Muslim should wish for his neighbor what he wishes for himself. He should control his anger. He should not eat if his neighbor is going hungry, i.e., he should share with his neighbor.
In short, a Muslim should try to be even-tempered, generous, just, and truthful. On Judgment Day, all these good deeds will be weighed against his bad deeds, and if the good deeds are more, he/she will be rewarded in Paradise.
This is only the briefest of outlines.
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