“What, then, is necessary for a Christian to believe?” asks the Heidelberg Catechism. “All that is promised us in the gospel, which the articles of our catholic, undoubted Christian faith teach us in summary,” is the reply. Though this creed was not penned by the Apostles, it summarizes their teaching with simplicity, brevity, and beauty. Originally used as a baptismal formula in the second century, it reached its present form in the sixth. It gives a concise expression of the fundamentals of historic Christianity.
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;
the third day He rose 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,
the holy, catholic Church,
the communion of saints,
the forgiveness of sins,
the resurrection of the body,
and the life everlasting.
This creed is an accurate and majestic formulation of the historic faith of orthodox Christianity. Originating at the Council of Nicea (AD 325), and revised at the Council of Constantinople (AD 381), it affirmed the biblical doctrine of the Trinity and the Person of Christ in opposition to various heresies, especially Arianism. The Western Church added the article on the procession of the Holy Spirit from Christ, “and the Son” (Latin: filioque) when it was adopted in its present form at the Council of Toledo (AD 589).
I 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 worlds; 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 on 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 I 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 worshiped and glorified; who spoke by the prophets.
And I believe one holy catholic and apostolic Church. I acknowledge one baptism for the remission of sins; and I look for the resurrection of the dead, and the life of the world to come.
This creed has been named after Athanasius (AD 293–373), the champion of orthodoxy over against the Arian heresy. Although he did not write it, the name persists because it was commonly ascribed to him by the Medieval Church. Being of Western origin, the creed first appeared in the early sixth century. Although the author is unknown, it embodied the teaching of Augustine (AD 354–430) in his book De Trinitate, as well as the decisions of the Council of Chalcedon on the Person of Christ (AD 451). Written in rhythmic cadences, this creed has been chanted in public worship by some churches. It is the fullest ecclesiastical statement of the truths of the Trinity and the Person of Christ.
 Whosoever will be saved, before all things it is necessary that he hold the catholic faith;  Which faith unless every one do keep whole and undefiled, without doubt he shall perish everlastingly.
 And the catholic faith is this: That we worship one God in Trinity, and Trinity in Unity;  Neither confounding the persons, nor dividing the substance.  For there is one person of the Father, another of the Son, and another of the Holy Spirit.  But the Godhead of the Father, of the Son, and of the Holy Spirit is all one, the glory equal, the majesty co-eternal.
 Such as the Father is, such is the Son, and such is the Holy Spirit.  The Father uncreated, the Son uncreated, and the Holy Spirit uncreated.  The Father incomprehensible, the Son incomprehensible, and the Holy Spirit incomprehensible.  The Father eternal, the Son eternal, and the Holy Spirit eternal.  And yet they are not three eternals, but one eternal.  As also there are not three uncreated nor three incomprehensibles, but one uncreated and one incomprehensible.  So likewise the Father is almighty, the Son almighty, and the Holy Spirit almighty;  And yet they are not three almighties, but one almighty.
 So the Father is God, the Son is God, and the Holy Spirit is God;  And yet they are not three Gods, but one God.  So likewise the Father is Lord, the Son Lord, and the Holy Spirit Lord;  And yet they are not three Lords, but one Lord.  For like as we are compelled by the Christian truth to acknowledge every Person by himself to be God and Lord;  So are we forbidden by the catholic religion to say: There are three Gods or three Lords.
 The Father is made of none, neither created nor begotten.  The Son is of the Father alone; not made nor created, but begotten.  The Holy Spirit is of the Father and of the Son; neither made, nor created, nor begotten, but proceeding.  So there is one Father, not three Fathers; one Son, not three Sons; one Holy Spirit, not three Holy Spirits.  And in this Trinity none is before, or after another; none is greater, or less than another.  But the whole three persons are co-eternal, and co-equal.  So that in all things, as said before, the Unity in Trinity and the Trinity in Unity is to be worshipped.  He therefore that will be saved must thus think of the Trinity.
The Person of Christ
 Furthermore it is necessary to everlasting salvation that he also believe rightly the incarnation of our Lord Jesus Christ.  For the right faith is that we believe and confess that our Lord Jesus Christ, the Son of God, is God and man.
 God of the substance of the Father, begotten before the worlds; and man of the substance of His mother, born in the world.  Perfect God and perfect man, of a reasonable soul and human flesh subsisting.  Equal to the Father as touching His Godhead, and inferior to the Father as touching His manhood.
 Who, although He is God and man, yet He is not two, but one Christ.  One, not by conversion of the Godhead into flesh, but by taking of the manhood into God.  One altogether, not by confusion of substance, but by unity of person.  For as the reasonable soul and flesh is one man, so God and man is one Christ;  Who suffered for our salvation, descended into hell, rose again the third day from the dead;  He ascended into heaven, He sits on the right hand of the Father, God Almighty;  From there He shall come to judge the living and the dead.  At whose coming all men shall rise again with their bodies;  And shall give account of their own works.  And they that have done good shall go into life everlasting, and they that have done evil into everlasting fire.
 This is the catholic faith, which unless a man believe faithfully, he cannot be saved.