Hi,
The Foundation is God.
There is one God.
There are three persons. God the Father, God the Son, and God the Holy Spirit.
This is the teaching of the Trinity. This seems to be the biggest difficulty that Muslims have understanding.
Some of it is language, there is nothing that perfectly represents the way God is. Even the word persons is different than how we tend to think of it. We tend to think of a person as separate from other persons but that isn't the way God is. He is one, not three separate persons but three united.
It may be helpful, since the explanation is so old to go to the origin of the word "person". It comes from a Latin word, persona. Now the persona is a mask that an actor would wear to represent a character. In one play, an actor would often be several different characters or personas. He might even dialogue with himself, by alternately holding up different masks and changing his aspect. Even though he had several personas during the play, there was only the one actor.
Now the example isn't perfect, but it is more what was being taught by God in three persons than what most would realize without going into it.
If you get to God being different persons but limit him to one at a time, that is called modalism.
A helpful resource to understand the Trinity is the
Anthanasian Creed.
Jesus Christ is true God and true man, each fully, completely, and undividely. He has always existed but he has not always been a man. He was born of a virgin, having no earthly father. The reason he came was because no person could be righteous, no man could perfectly keep the Law. He came and fulfilled the Law becoming a perfect sacrifice for the sins of the world. Even death had no power over him and he rose again and ascended to heaven awaiting the day when he will return.
The Holy Spirit is with us. He convicts us of our sins, making us aware of our need for God. After we have quit resisting and fighting against God, the Holy Spirit indwells us. He changes us so that we can truly do good and love God and man.
God has revealed himself to us. He can be seen through his creation, though it is not usually believed that people see him clearly enough to be saved through what is called general revelation. He also reveals himself through the Bible. The Bible is a progressive revelation of God. Revealing to each succeeding group more of his plan. The Bible is scripture, though written by the hands of men, it is God-breathed. We talk of it being inspired, but it would actually be more correct to say it is spired. The original Bible was written in Hebrew, Aramaic, and Greek.
Christianity splits somewhat on how they see the Bible. Roman Catholics and Orthodox would see it as a part of Holy Tradition. They do not get their authoritative teachings only from the Bible, but also through what they believe the church fathers taught and continue to teach. Most of those whom are generally referred to as Protestants would use the Bible as the sole norm and source of authoritative teachings. Protestants would split on whether they believe each word is inspired and the truth, or if they believe God's truth is in the Bible, but not necessarily is every word perfect.
For a very readable explanation of doctrines, I would recommend Wayne Grudem's book, "Bible Doctrine." He does a good job of presenting doctrines and giving explanations, and unlike some authors, he is very readable. I actually would disagree with Mr. Grudem on a few things, like his teachings on the charismatic gifts, but if you read Grudem he is fair and presents more than a "this is the only way" type of book. I think it would be $20 that would save you a lot of confusion.
Marv
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