I believe in what historic Christianity has taught for nearly 2,000 years. There have always been plenty of people who profess to believe the same thing, but have not let their lives reflect their claimed beliefs. Jesus of the Bible is full of mercy and compassion, unlike many who say they follow him. He didn't condone sin, but also didn't condemn sinners - He offered forgiveness and mercy at every turn. The only people Jesus blasted in the Gospels were the extremely religious leaders who He compared to 'whitewashed tombstones.'
That being said, my core beliefs in God are reflected in the Nicene Creed, as follows.

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 catholic and apostolic 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. Amen.