The Early Church Fathers - The Early Creed and Trinity
This is a brief page that provides very clearly where the very first Creed of Christianity was initially written. It was first laid out in detail by Irenaeus and the concept is that it was the Christians that held these foundational doctrines. It is based on the FAITH that was handed down from the Apostles, and their disciples. What is also awesome is that it provides early examples of the Trinty (Father, Son, and Holy Spirit) that destroy the lies that the concept of the Triune God was not formed until much later by Constantine and the Roman Catholic Church.
Irenaeus [a.d. 120–202]
Chapter X.--Unity of the faith of the Church throughout the whole world.
http://www.ccel.org/ccel/schaff/anf01.ix.ii.xi.html
1. The Church, though dispersed through our the whole world, even to the ends of the earth, has received from the apostles and their disciples this faith: [She believes] in one God, the Father Almighty, Maker of heaven, and earth, and the sea, and all things that are in them; and in one Christ Jesus, the Son of God, who became incarnate for our salvation; and in the Holy Spirit, who proclaimed through the prophets the dispensations of God, and the advents, and the birth from a virgin, and the passion, and the resurrection from the dead, and the ascension into heaven in the flesh of the beloved Christ Jesus, our Lord, and His [future] manifestation from heaven in the glory of the Father "to gather all things in one," and to raise up anew all flesh of the whole human race, in order that to Christ Jesus, our Lord, and God, and Saviour, and King, according to the will of the invisible Father, "every knee should bow, of things in heaven, and things in earth, and things under the earth, and that every tongue should confess" to Him, and that He should execute just judgment towards all; that He may send "spiritual wickednesses," and the angels who transgressed and became apostates, together with the ungodly, and unrighteous, and wicked, and profane among men, into everlasting fire; but may, in the exercise of His grace, confer immortality on the righteous, and holy, and those who have kept His commandments, and have persevered in His love, some from the beginning [of their Christian course], and others from [the date of] their repentance, and may surround them with everlasting glory.
Next we see Clement of Rome make clear reference to One God, One Christ, and One Holy Spirit.
Clement of Rome [a.d. 30–100.]
Chapter XLVI.--Let us cleave to the righteous: your strife is pernicious.
http://www.ccel.org/ccel/schaff/anf01.ii.ii.xlvi.html
Such examples, therefore, brethren, it is right that we should follow; since it is written, "Cleave to the holy, for those that cleave to them shall [themselves] be made holy."And again, in another place, [the Scripture] saith, "With a harmless man thou shalt prove thyself harmless, and with an elect man thou shalt be elect, and with a perverse man thou shalt show thyself perverse." Let us cleave, therefore, to the innocent and righteous, since these are the elect of God. Why are there strifes, and tumults, and divisions, one Christ? Is there not one Spirit of grace poured out upon us? And have we not one calling in Christ?
Here we see Cyprian use the term Trinity nearly a hundred years before the Nicene Council. He brings forth and the concept of Father, Son, Holy Spirit and that they are all required for the remission of sin.
Cyprian [a.d. 200–258.]
Epistle LXXII.- To Jubaianus, Concerning the Baptism of Heretics.
http://www.ccel.org/ccel/schaff/anf05.iv.iv.lxxii.html
18. Finally, when, after the resurrection, the apostles are sent by the Lord to the heathens, they are bidden to baptize the Gentiles "in the name of the Father, and of the Son, and of the Holy Ghost." How, then, do some say, that a Gentile baptized without, outside the Church, yea, and in opposition to the Church, so that it be only in the name of Jesus Christ, everywhere, and in whatever manner, can obtain remission of sin, when Christ Himself commands the heathen to be baptized in the full and united Trinity? Unless while one who denies Christ is denied by Christ, he who denies His Father whom Christ Himself confessed is not denied; and he who blasphemes against Him whom Christ called His Lord and His God, is rewarded by Christ, and obtains remission of sins, and the sanctification of baptism!