The Ancient Creeds
Apostles’ Creed
The Apostles’ Creed was not written by the Apostles themselves, but was developed over time by the ancient churches (A.D. 100–700). We call it the Apostles’ Creed because all the phrases come straight out of the doctrine of the Apostles in the Scriptures. The first official version of what would later become the Apostles’ Creed was used in Rome in the 2nd century as a way to instruct converts who were preparing for baptism (cf. Eph 4:4–6).

The Apostles’ Creed confesses in a basic way that the Christian believes there is one God who exists in three persons. We call this the doctrine of the Holy Trinity. In doing this, the Creed has three simple parts. In the first part we confess to believe in God the Father, our Creator; in the second part we confess to believe in Jesus Christ, our Redeemer; and in the third part we confess to believe in the Holy Spirit, our Sanctifier.
____________________
I believe in God the Father Almighty, Maker of heaven and earth.
And in Jesus Christ, His only begotten Son, our Lord; who was conceived by the Holy Spirit, born of the virgin Mary; suffered under Pontius Pilate; was crucified, dead, and buried; He descended into hell;1 the third day He rose again from the dead; He ascended into heaven, and sits at the right hand of God the Father Almighty; from there He shall come to judge the living and the dead.
I believe in the Holy Spirit; a holy catholic2 Church, the communion of saints; the forgiveness of sins; the resurrection of the body; and the life everlasting. Amen.

1 This phrase has been understood in the Reformed Churches as meaning two things: as to the body of Jesus Christ, he descended into the state of death; as to the soul of Jesus Christ, he suffered the agonies of hell (Catechism of the Church of Geneva, Q&A 66, 67, 70; Westminster Confession of Faith 8.4; Westminster Larger Catechism, Q&A 50; Heidelberg Catechism, Q&A 44).
2 Catholic means universal, that is, that there is one Church across all times, places, and peoples (Belgic Confession, art. 27; Heidelberg Catechism, Q&A 54).

Nicene Creed
The Nicene Creed was first written in A.D. 325 at the first ecumenical Council of Nicea, a city in modern–day Turkey. Representatives from throughout the Church gathered to respond to and reject the false teaching of a preacher named Arius. Arius taught that the Son of God was not eternal, but was the first creation of God the Father. What this meant was that Jesus Christ was less divine than God the Father. Later, at the second ecumenical Council of Constantinople in 381, the churches responded to the false teaching of the Macedonians who said that the Holy Spirit was not fully God. Thus, the phrases about the Holy Spirit in the Nicene Creed were added to complete this great creed. Because of its depth of teaching and purpose in protecting the Church, the Nicene Creed is the most important of the Christian creeds.

In the Nicene Creed, we confess to believe in God the Father, God the Son, and God the Holy Spirit, as well as confess the Church of Christ.
____________________
We believe in one God, the Father Almighty, Maker of heaven and earth, and of all things visible and invisible.

And in one Lord Jesus Christ, the only-begotten Son of God, begotten of the Father before all ages; God of God, Light of Light, very God of very God; begotten, not made, being of one substance with the Father, by whom all things were made. Who, for us men and for our salvation, came down from heaven and was Incarnate by the Holy Spirit of the virgin Mary,
and was made man; and was crucified also for us under Pontius Pilate; He suffered and was buried; and the third day He rose again, according to the Scriptures; and ascended into heaven, and sits at the right hand of the Father; and He shall come again, with glory, to judge the living and the dead; whose kingdom shall have no end.
And we believe in the Holy Spirit, the Lord and Giver of life; who proceeds from the Father and the Son; who with the Father and the Son together is worshipped and glorified; who spoke by the prophets.
And we believe one holy catholic and apostolic1 Church. We acknowledge one baptism for the remission of sins;2 and we look for the resurrection of the dead, and the life of the world to come. Amen.

1 “Apostolic” means built upon the doctrinal foundation of the apostles and prophets (Eph 2:20).
2 Baptism is the visible sign and seal of this invisible work of God in washing our souls (Acts 22:16; Heidelberg Catechism Q&A 69-73).

Athanasian Creed
The Athanasian Creed is named after St. Athanasius (A.D. 296–373), a deacon in the church in Alexandria, Egypt. Athanasius was one of the staunchest opponents of the teachings of Arius at the Council of Nicea. Like the Apostles’ Creed, the Athanasian Creed was most likely not written by its namesake, but was taken from his writings against Arius. These different parts of his writings were later compiled into a beautifully poetic creed sometime between A.D. 500–800. It is divided into two parts. The first part confesses a detailed explanation of the doctrine of the Trinity, that we believe and worship one God in Unity and Unity in Trinity. In the second part, it confesses a detailed explanation of the doctrine of the Person of Christ, that there is one Lord Jesus Christ, who is both perfect God and perfect man. Both of these parts of the creed open with a statement of the necessity to believe in the Triune nature of God and two natures of Christ to have salvation.
____________________
1. Whosoever will be saved, before all things it is necessary that he hold the catholic faith;
2. Which faith except every one do keep whole and undefiled, without doubt he shall perish everlastingly.
3. And the catholic faith is this: That we worship one God in Trinity, and Trinity in Unity;
4. Neither confounding the persons, nor dividing the substance.
5. For there is one person of the Father, another of the Son, and another of the Holy Spirit.
6. But the Godhead of the Father, of the Son, and of the Holy Spirit is all one, the glory equal, the majesty co-eternal.
7. Such as the Father is, such is the Son, and such is the Holy Spirit.
8. The Father is uncreated, the Son is uncreated, and the Holy Spirit is uncreated.
9. The Father is incomprehensible, the Son is incomprehensible, and the Holy Spirit is incomprehensible.
10. The Father is eternal, the Son is eternal, and the Holy Spirit is eternal.
11. And yet there are not three eternals, but one eternal.
12. As also there are not three uncreated nor three incomprehensibles, but one uncreated and one incomprehensible.
13. So likewise the Father is almighty, the Son is almighty, and the Holy Spirit is almighty;
14. And yet there are not three almighties, but one almighty.
15. So the Father is God, the Son is God, and the Holy Spirit is God;
16. And yet they are not three Gods, but one God.
17. So likewise the Father is Lord, the Son is Lord, and the Holy Spirit is Lord;
18. And yet they are not three Lords, but one Lord.
19. For like as we are compelled by the Christian verity to acknowledge every person1 by himself to be God and Lord;
20. So we are forbidden by the catholic religion to say: There are three Gods or three Lords.
21. The Father is made of none, neither created nor begotten.
22. The Son is of the Father alone; not made nor created, but begotten.
23. The Holy Spirit is of the Father and of the Son; neither made, nor created, nor begotten, but proceeding.
24. So there is one Father, not three Fathers; one Son, not three Sons; one Holy Spirit, not three Holy Spirits.
25. And in this Trinity none is before, or after another; none is greater, or less than another.
26. But the whole three persons are co-eternal, and co-equal.
27. So that in all things, as aforesaid, the Unity in Trinity and the Trinity in Unity is to be worshipped.
28. He therefore that will be saved must thus think of the Trinity.
29. Furthermore it is necessary to everlasting salvation that he also believe rightly the incarnation of our Lord Jesus Christ.
30. For the right faith is that we believe and confess that our Lord Jesus Christ, the Son of God, is God and man.
31. God of the substance of the Father, begotten before the worlds; and man of the substance of His mother, born in the world.
32. Perfect God and perfect man, of a reasonable soul and human flesh subsisting.
33. Equal to the Father as touching His Godhead, and inferior to the Father as touching His manhood.
34. Who, although He is God and man, yet He is not two, but one Christ.
35. One, not by conversion of the Godhead into flesh, but by taking of the manhood into God.
36. One altogether, not by confusion of substance, but by unity of person.
37. For as the reasonable soul and flesh is one man, so God and man is one Christ.
38. Who suffered for our salvation, descended into hell, rose again the third day from the dead;
39. He ascended into heaven, He sits at the right hand of the Father, God Almighty;
40. From there He shall come to judge the living and the dead.
41. At whose coming all men shall rise again with their bodies;
42. And shall give account of their own works.
43. And they that have done good shall go into life everlasting. And they that have done evil into everlasting fire.
44. This is the catholic faith, which except a man believe faithfully, he cannot be saved.

1 That is, every Person of the Trinity, not every human person

Definition of Chalcedon
The Definition of Chalcedon was written in A.D. 451 at the fourth ecumenical council of Chalcedon, a modern–day city in Turkey. At this council, the churches of the ancient world gathered to respond to several different false teachings about who our Lord Jesus Christ is.

One false teaching was Nestorianism, which taught that Christ’s two “natures”—his divinity and humanity—were divided so that Christ was two completely separate Persons and not united in the one Person of Christ. Another heresy was that of Eutychianism, which taught that Christ’s natures were so united in his Person, that the divine nature swallowed up the human nature, thus leaving one mixed nature. The third heresy was Apollinarianism, which taught that Jesus had a true human body and a “lower soul” (which animals have), but that the eternal logos (the “Word” of John 1:1) replaced the “higher soul” (which only humans have). This meant that Jesus Christ was not as fully human as we are.

Again, theologians, pastors, and church leaders had to meet to respond to false teaching and confess what the Word of God taught on this vital doctrine of Christ. The Definition is one paragraph in which the Church confesses to believe in one Lord Jesus Christ, who has two natures, a divine and a human.

In the Belgic Confession of Faith, article 9, the Reformed churches confess that “we do willingly receive the three creeds, namely, that of the Apostles, of Nicea, and of Athanasius; likewise that which, conformable thereunto, is agreed upon by the ancient fathers.” The Definition of Chalcedon is a part of those "conformable" doctrines from the ancient church.
____________________
We, then, following the holy Fathers, all with one consent, teach men to confess one and the same Son, our Lord Jesus Christ: the same perfect in Godhead and also perfect in manhood; truly God and truly man, of a rational soul and body; consubstantial with the Father according to the Godhead, and consubstantial with us according to the Manhood; in all things like unto us, without sin; begotten before all ages of the Father according to the Godhead, and in these latter days, for us and for our salvation, born of the Virgin Mary, the mother of God1 according to the Manhood; One and the same Christ, Son, Lord, Only-begotten, to be acknowledged in two natures, inconfusedly, unchangeably, indivisibly, inseparably; the distinction of the natures being by no means taken away by the union, but rather the property of each nature being preserved, and concurring in one Person and Subsistence, not parted or divided into two persons, but one and the same Son, only begotten, God the Word, the Lord Jesus Christ; As the prophets from the beginning have declared concerning him, and the Lord Jesus Christ himself has taught us, and the Creed of the holy Fathers has handed down to us.

1 The title “mother of God” (Greek, theotokos ) was used to express that Jesus derived a true human nature from Mary.