This was formulated at the of Nicaea (325 a.d.). It was inspired by the Syro-Palestinian and Eusebius’ creeds. It mentioned for the first time the word , meaning “the same substance.” This term was condemned during the crisis of of Samosata, but Alexander of Alexandria and Athanasius gave the true meaning. The is thus:

We believe in one God, the Father, the ruler of all, the creator of all things visible and invisible, and in one Lord, Jesus Christ the Son of God, begotten as the only Son out of the Father, that is, out of the substance of the Father, God from God, light from Light, true God from true God, begotten not created, with the Father, the one through . . .

The Nicene is recited prior to baptism; after the fifth century, Peter the Fuller introduced it into the liturgy after the gospel reading as a proclamation of faith.

In the of Constantinople (381 a.d.), the following paragraph was added: “We believe in the Holy Spirit . . .” It became a standard declaration of faith for all Christians. The modification of one word—the filioque, in the 11th century—contributed to the final schism between the East and the West. This schism is known as the filioque crisis.