Hey, I am a Christian. To specify, I believe what is written in the Nicean creed.
"We believe in one God,
the Father, the Almighty,
maker of heaven and earth,
of all that is, seen and unseen.*
We believe in one Lord, Jesus Christ,
the only Son of God,
eternally begotten of the Father,
God from God, Light from Light,
true God from true God,
begotten, not made,
of one Being with the Father.
Through him all things were made.
For us and for our salvation
he came down from heaven:
by the power of the Holy Spirit
he became incarnate from the Virgin Mary,
and was made man.
For our sake he was crucified under Pontius Pilate;
he suffered death and was buried.
On the third day he rose again
in accordance with the Scriptures;
he ascended into heaven
and is seated at the right hand of the Father.
He will come again in glory to judge the living and the dead,
and his kingdom will have no end.*
We believe in the Holy Spirit, the Lord, the giver of life,
who proceeds from the Father and the Son.
With the Father and the Son he is worshiped and glorified.
He has spoken through the Prophets.
We believe in one holy ... Church.
We acknowledge one baptism for the forgiveness of sins.
We look for the resurrection of the dead,
and the life of the world to come."
As for why I believe this, let me give it to you in parts. First, the reason I believe the world was created is because nothing can come out of nonexistence, and because if the universe has, in fact, always been here then I wonder at how there are stars that still burn and how entropy hasn't worn all activity away. This is my reason for a God, but at this point I am still at the level of a deist. The reason I believe in a God that is intimately involved with his creation is that we, humans, all have a sense of right and wrong, a sense of how we should behave. If the creator of the universe wasn't personally involved with us, he wouldn't really care about how we behaved and wouldn't have given us this sense of good and bad (in terms of morality). And to avoid an avalanche of questions and refutes, I will pause here to answer/reply to your questions/arguments that I know are just itching to spew from your debate loving selves. Also, please be respectful and try not to be caustic in your replies. This forum is for people to share what they believe and why, not for people to harass others for thinking differently.