The Early Church faced many false teachings and distorted thinking. In 325 A.D., the leaders of the local Christian congregations (called "bishops" as in 1 Timothy 3:1-2) came from all over the Roman Empire to meet. Together they wrote a brief statement to describe what true Christians believed about God: Father, Son and Holy Spirit.  The leaders met at Nicea, in modern Turkey. "Credo" is the Latin word for "I believe." With the minor additions agreed upon in 381 A.D., it is thus called...

The Nicene Creed

I believe in one God,
the Father, the Almighty,
maker of heaven and earth,
of all that is, visible and invisible. 

I 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 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. 

I 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.

* means "worldwide, all true followers united in Jesus Christ"