A sermon on the mystery of the Trinity, three Persons in one God and one God in three Persons. There is no obedience or subordination within the Trinity, be all three are co-eternal and co-equal. Each Person is fully God and all three are one only God.
The first half of the Athasian Creed:
"Whosoever will be saved, before all things it is necessary
that he hold the Catholic Faith. Which Faith except everyone 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 Ghost. But the Godhead
of the Father, of the Son and of the Holy Ghost is all One, the Glory Equal,
the Majesty Co-Eternal.
"Such as the Father is, such is the Son, and such is the Holy Ghost. The Father Uncreate, the Son Uncreate, and the Holy Ghost Uncreate. The Father Incomprehensible, the Son Incomprehensible, and the Holy Ghost Incomprehensible. The Father Eternal, the Son Eternal, and the Holy Ghost 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 Ghost Almighty. And yet they are not Three Almighties but One Almighty.
"Such as the Father is, such is the Son, and such is the Holy Ghost. The Father Uncreate, the Son Uncreate, and the Holy Ghost Uncreate. The Father Incomprehensible, the Son Incomprehensible, and the Holy Ghost Incomprehensible. The Father Eternal, the Son Eternal, and the Holy Ghost 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 Ghost Almighty. And yet they are not Three Almighties but One Almighty.
"So the Father is God, the Son is God, and the Holy Ghost is
God. And yet they are not Three Gods, but One God. So likewise the Father is
Lord, the Son Lord, and the Holy Ghost Lord. And yet not Three Lords but One
Lord. For, like as we are compelled by the Christian verity to acknowledge
every Person by Himself to be God and Lord, so are we forbidden by the Catholic
Religion to say, there be 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 Ghost 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 Ghost, not Three Holy Ghosts. And in this Trinity none is
afore or after Other, None is greater or less than Another, but the whole Three
Persons are Co-eternal together, and Co-equal. So that in all things, as is
aforesaid, the Unity in Trinity, and the Trinity in Unity, is to be worshiped.
He therefore that will be saved, must thus think of the Trinity."
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