Nicene Creed:
I believe in one God,
the Father almighty,
maker of heaven and earth,
of all things visible and invisible.
I believe in one Lord Jesus Christ,
the Only Begotten Son of God,
born of the Father before all ages.
God from God, Light from Light,
true God from true God,
begotten, not made, consubstantial with the Father;
through him all things were made.
For us men and for our salvation
he came down from heaven,
and by the Holy Spirit was incarnate of the Virgin Mary,
and became man.
For our sake he was crucified under Pontius Pilate,
he suffered death and was buried,
and rose again on the third day
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 (through) the Son],
who with the Father and the Son is adored and glorified,
who has spoken through the prophets.
I believe in one, holy, catholic and apostolic Church.
I confess one Baptism for the forgiveness of sins
and I look forward to the resurrection of the dead
and the life of the world to come.
In short: we believe the Jews received the Old Covenant, and that Christ established the New Covenant, making Jews and Gentiles one. We do not believe the Scriptures are errant, as Muslims do. We believe they are accurate.
On account of the Jews having the Old Covenant and Christ establishing the New, we have Old and New Testament. Jesus came, suffered, and died for us.
We believe in the teachings of Jesus Christ. Muslims do not have the teachings of Jesus Christ, as they say the records are messed up. We believe in His Teachings.
We also believe that the Word is Jesus Christ (as do Muslims), but we also believe that God has His Word. We believe Jesus is the begotten Son of the Father, and the third Person of the Trinity is the Holy Spirit, who is a Person and not an it.
We obviously don’t think Mohammed is the “light” or any such things, but that he is a false prophet.
Naturally we reject the Qur’an and the Hadith as genuine revelation.
We believe Jesus established the Catholic Church, His Mystical Body, and that we are protected from error by the Holy Spirit.
We do not believe in 3 Gods, but in 1 God, who is 3 Persons in one Being.
The Orthodox and Catholic has much in common. Orthodox reject the part in the creed posted above in [ ] and do not follow the Bishop of Rome as holding certain authority we say he has as head of the Church. We all believe that Mary is the Theotokos, mother of God, not merely mother of Christ.