
There is only one God, creator of everything. Earlier Christians were willing to die horrible and painful deaths rather than renounce this fact.
John 17:3 " Now this is eternal life: that they may know you, the only true God. and Jesus Christ, whom you have sent."
Isaiah 43:10 "You are my witnesses," declares the Lord, "and my servant whom I have chosen so that you may know and believe me and understand that I am he. Before me no god was formed, nor will there be one after me."
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200 These are the words with which the Niceno- Constantinopolitan Creed begins. The confession of God's oneness, which has its roots in the divine revelation of the Old Covenant, is inseparable from the profession of God's existence and is equally fundamental. God is unique; there is only one God: "The Christian faith confesses that God is one in nature, substance and essence."
201 To Israel, his chosen, God revealed himself as the only One: "Hear, O Israel: The LORD our God is one LORD; and you shall love the LORD your God with all your heart, and with all your soul, and with all your might." Through the prophets, God calls Israel and all nations to turn to him, the one and only God: "Turn to me and be saved, all the ends of the earth! For I am God, and there is no other.. . To me every knee shall bow, every tongue shall swear. 'Only in the LORD, it shall be said of me, are righteousness and strength.'"
202 Jesus himself affirms that God is "the one Lord" whom you must love "with all your heart, and with all your soul, and with all your mind, and with all your strength". At the same time Jesus gives us to understand that he himself is "the Lord". To confess that Jesus is Lord is distinctive of Christian faith. This is not contrary to belief in the One God. Nor does believing in the Holy Spirit as "Lord and giver of life" introduce any division into the One God: We firmly believe and confess without reservation that there is only one true God, eternal infinite (immensus) and unchangeable, incomprehensible, almighty and ineffable, the Father and the Son and the Holy Spirit; three persons indeed, but one essence, substance or nature entirely simple.
228 "Hear, O Israel, the LORD our God is one LORD..." (Dt 6:4; Mk 12:29). "The supreme being must be unique, without equal. . . If God is not one, he is not God"
The one God has three individual persons: The Father, The Son, and the Holy Spirit. Jesus Christ, Savior of the world is the second person of what is called The Trinity. He is fully God.
Matthew 28:19 - Go therefore and make disciples of all nations, baptising them in the name of the Father, and of the Son, and of the Holy Spirit.
Philippians 2:10-11 - That at the name of Jesus every knee should bow, in heaven and on earth and under the earth, and every tongue confess that Jesus Christ is Lord, to the Glory of God the Father.
Isaiah 45:19-24 - I have not spoken in secret, from somewhere in a land of darkness: I have not said to Jacob's descendants, "Seek me in vain" I the Lord, speak the truth: I declare what is right. "Gather together and come; assemble, you fugitives from the nations. Ignorant are those who carry about idols of wood, who pray to gods that cannot save. Declare what is to be, present it - let them take counsel together. Who foretold this long ago, who declared it from the distant past? Was it not I, the Lord? And there is no God apart from me. A righteous God and a Savior, there is none but me. Turn to me and be saved, all you ends of the earth; for I am God, and there is no other. By myself I have sworn, my mouth has uttered in all integrity a word that will not be revoked: before me every knee will bow; by me every tongue will swear. They will say of me, "In the Lord alone are righteosness and strength.
John 8:58-59 - I tell you the truth," Jesus answered, "Before Abraham was born, I Am!" At this point they picked up stones to stone him but Jesus hid himself, slipping away from the temple grounds.
2 Corinthians 13:14 - May the grace of the Lord Jesus Christ, and the love of God, and the fellowship of the Holy Spirit be with you all.
John 20:28 - Thomas said to him, "My Lord and my God!
Isaiah 44:6 - This is what the Lord says. Israel's King and Redeemer, the Lord Almighty: I am the First and the Last; apart from me there is no God.
Isaiah 41:4 - Who has done this and carried it through, calling forth the generations from the beginning, I the Lord - with the first of them and with the last- I am He.
Isaiah 48:12 - Listen to me, O Jacob, Israel, whom I have called: I am He: I am the First and I am the Last.
Revelation 1:8 - I am the Alpha and the Omega, says the Lord, who is and who was and who is to come, the Almighty.
Revelations 1:17 - When I saw him, I fell at his feer as though dead. Then he placed his right hand on me and the Living One. I was dead, and behold, I am alive forever and ever! And I hold the keys of death and Hades!
Revelation 2:8 - To the Angel of the Church in Smyrna write: These are the words of him who is the First and the Last, who died and came to life again.
Revelation 22:12-23 - Behold I am coming again! My reward is with me, and I will give to everyone according to what he has done. I am the Alpha and the Omega, the First and the Last, the Beginning and the End.
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253 The Trinity is One. We do not confess three Gods, but one God in three persons, the "consubstantial Trinity". The divine persons do not share the one divinity among themselves but each of them is God whole and entire: "The Father is that which the Son is, the Son that which the Father is, the Father and the Son that which the Holy Spirit is, i.e. by nature one God."In the words of the Fourth Lateran Council (1215), "Each of the persons is that supreme reality, viz., the divine substance, essence or nature."
254 The divine persons are really distinct from one another. "God is one but not solitary." "Father", "Son", "Holy Spirit" are not simply names designating modalities of the divine being, for they are really distinct from one another: "He is not the Father who is the Son, nor is the Son he who is the Father, nor is the Holy Spirit he who is the Father or the Son." They are distinct from one another in their relations of origin: "It is the Father who generates, the Son who is begotten, and the Holy Spirit who proceeds." The divine Unity is Triune.
255 The divine persons are relative to one another. Because it does not divide the divine unity, the real distinction of the persons from one another resides solely in the relationships which relate them to one another: "In the relational names of the persons the Father is related to the Son, the Son to the Father, and the Holy Spirit to both. While they are called three persons in view of their relations, we believe in one nature or substance."Indeed "everything (in them) is one where there is no opposition of relationship." "Because of that unity the Father is wholly in the Son and wholly in the Holy Spirit; the Son is wholly in the Father and wholly in the Holy Spirit; the Holy Spirit is wholly in the Father and wholly in the Son."
256 St. Gregory of Nazianzus, also called "the Theologian", entrusts this summary of Trinitarian faith to the catechumens of Constantinople: Above all guard for me this great deposit of faith for which I live and fight, which I want to take with me as a companion, and which makes me bear all evils and despise all pleasures: I mean the profession of faith in the Father and the Son and the Holy Spirit. I entrust it to you today. By it I am soon going to plunge you into water and raise you up from it. I give it to you as the companion and patron of your whole life. I give you but one divinity and power, existing one in three, and containing the three in a distinct way. Divinity without disparity of substance or nature, without superior degree that raises up or inferior degree that casts down. . . the infinite co-naturality of three infinites. Each person considered in himself is entirely God. . . the three considered together. . . I have not even begun to think of unity when the Trinity bathes me in its splendour. I have not even begun to think of the Trinity when unity grasps me. .
261 The mystery of the Most Holy Trinity is the central mystery of the Christian faith and of Christian life. God alone can make it known to us by revealing himself as Father, Son and Holy Spirit.
262 The Incarnation of God's Son reveals that God is the eternal Father and that the Son is consubstantial with the Father, which means that, in the Father and with the Father the Son is one and the same God.
263 The mission of the Holy Spirit, sent by the Father in the name of the Son (Jn 14:26) and by the Son "from the Father" (Jn 15:26), reveals that, with them, the Spirit is one and the same God. "With the Father and the Son he is worshipped and glorified" (Nicene Creed).
264 "The Holy Spirit proceeds from the Father as the first principle and, by the eternal gift of this to the Son, from the communion of both the Father and the Son"
265 By the grace of Baptism "in the name of the Father and of the Son and of the Holy Spirit", we are called to share in the life of the Blessed Trinity, here on earth in the obscurity of faith, and after death in eternal light
266 "Now this is the Catholic faith: We worship one God in the Trinity and the Trinity in unity, without either confusing the persons or dividing the substance; for the person of the Father is one, the Son's is another, the Holy Spirit's another; but the Godhead of the Father, Son and Holy Spirit is one, their glory equal, their majesty coeternal"
267 Inseparable in what they are, the divine persons are also inseparable in what they do. But within the single divine operation each shows forth what is proper to him in the Trinity, especially in the divine missions of the Son's Incarnation and the gift of the Holy Spirit.
Some people try to say that Jesus was not always the Son. This is not true, Jesus was always the Son in the Godhead since the very Beginning.
1 John - This is how God showed his love among us: He sent his One and Only Son into the world that we might live through him.
John 1:11-12 - In the beginning was the Word and the Word was with God, and the Word was God. He was with God in the beginning.
John 1:14 - The Word became flesh and made his dwelling among us. We have seen his glory, the glory of the One and Only who came from the Father, full of grace and truth.
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441 In the Old Testament, "son of God" is a title given to the angels, the Chosen People, the children of Israel, and their kings. It signifies an adoptive sonship that establishes a relationship of particular intimacy between God and his creature. When the promised Messiah-King is called "son of God", it does not necessarily imply that he was more than human, according to the literal meaning of these texts. Those who called Jesus "son of God", as the Messiah of Israel, perhaps meant nothing more than this.
442 Such is not the case for Simon Peter when he confesses Jesus as "the Christ, the Son of the living God", for Jesus responds solemnly: "Flesh and blood has not revealed this to you, but my Father who is in heaven." Similarly Paul will write, regarding his conversion on the road to Damascus, "When he who had set me apart before I was born, and had called me through his grace, was pleased to reveal his Son to me, in order that I might preach him among the Gentiles..." "And in the synagogues immediately [Paul] proclaimed Jesus, saying, 'He is the Son of God.'" From the beginning this acknowledgment of Christ's divine sonship will be the centre of the apostolic faith, first professed by Peter as the Church's foundation.
443 Peter could recognize the transcendent character of the Messiah's divine sonship because Jesus had clearly allowed it to be so understood. To his accusers' question before the Sanhedrin, "Are you the Son of God, then?" Jesus answered, "You say that I am." Well before this, Jesus referred to himself as "the Son" who knows the Father, as distinct from the "servants" God had earlier sent to his people; he is superior even to the angels. He distinguished his sonship from that of his disciples by never saying "our Father", except to command them: "You, then, pray like this: 'Our Father'", and he emphasized this distinction, saying "my Father and your Father".
444 The Gospels report that at two solemn moments, the Baptism and the Transfiguration of Christ, the voice of the Father designates Jesus his "beloved Son".Jesus calls himself the "only Son of God", and by this title affirms his eternal pre-existence.He asks for faith in "the name of the only Son of God".In the centurion's exclamation before the crucified Christ, "Truly this man was the Son of God", that Christian confession is already heard. Only in the Paschal mystery can the believer give the title "Son of God" its full meaning.
454 The title "Son of God" signifies the unique and eternal relationship of Jesus Christ to God his Father: he is the only Son of the Father To be a Christian, one must believe that Jesus Christ is the Son of God
Some groups have been teaching that God once had a body. Except for Jesus, the Son, this i snot true. God a Spirit.
John 4:24 - God is a Spirit and his worshippers must worship in Spirit and in truth.
Luke 24:39 - Look at my hands and my feet. It is I myself. Touch me and see, a spirit does not have flesh and bones, as you see I have.