No. I am asking you to clarify exactly what you mean when you ask me to show you the doctrine of the Trinity in the Bible, and not its definition.
Here's the doctrine:
249 From the beginning, the revealed truth of the Holy Trinity has been at the very root of the Church's living faith, principally by means of Baptism. It finds its expression in the rule of baptismal faith, formulated in the preaching, catechesis and prayer of the Church. Such formulations are already found in the apostolic writings, such as this salutation taken up in the Eucharistic liturgy: "The grace of the Lord Jesus Christ and the love of God and the fellowship of the Holy Spirit be with you all."81
250 During the first centuries the Church sought to clarify her Trinitarian faith, both to deepen her own understanding of the faith and to defend it against the errors that were deforming it. This clarification was the work of the early councils, aided by the theological work of the Church Fathers and sustained by the Christian people's sense of the faith.
251 In order to articulate the dogma of the Trinity, the Church had to develop her own terminology with the help of certain notions of philosophical origin: "substance", "person" or "hypostasis", "relation" and so on. In doing this, she did not submit the faith to human wisdom, but gave a new and unprecedented meaning to these terms, which from then on would be used to signify an ineffable mystery, "infinitely beyond all that we can humanly understand".82
252 The Church uses (I) the term "substance" (rendered also at times by "essence" or "nature") to designate the divine being in its unity, (II) the term "person" or "hypostasis" to designate the Father, Son and Holy Spirit in the real distinction among them, and (III) the term "relation" to designate the fact that their distinction lies in the relationship of each to the others.
The dogma of the Holy Trinity
253 The Trinity is One. We do not confess three Gods, but one God in three persons, the "consubstantial Trinity".83 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."84 In the words of the Fourth Lateran Council (1215), "Each of the persons is that supreme reality, viz., the divine substance, essence or nature."85
254 The divine persons are really distinct from one another. "God is one but not solitary."86 "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."87 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."88 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."89 Indeed "everything (in them) is one where there is no opposition of relationship."90 "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."91
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 splendor. I have not even begun to think of the Trinity when unity grasps me. . .92
Wrong. The Christian Church fathers.
There was only one Church-the Catholic Church.
I have, in posts #2 and #109. It contradicts Psalms 51:5, Romans 3:10 and Romans 3:23.
Well, you call yourself a Catholic. Catholics believe in salvation by faith and works. Are you implying that you reject Catholic doctrine?
I am implying that you don't have any idea what the Catholic Church teaches, because Catholics do not believe in salvation by faith and works.
The problem is that this Mary is also identified as the mother of Jesus (Matthew 13:53-56).
Wrong.
I know. That is your key problem. If your tradition contradicts the Bible, you ignore the Bible and follow tradition.
Strike 2. We never ignore the Bible.
But what does Eve have to do with Mary?
God's creation. Mary is called the New Eve, where Eve disobeyed God and sinned, Mary obeyed God and did not.
Yes, there is, because you use them as mediators.
Why do you have a problem with intercessory prayer? Do you ever ask someone to pray for you?
Because you believe that Purgatory is ‘a place or condition of temporal punishment for those who, departing this life in God's grace, are not entirely free from venial faults, or have not fully paid the satisfaction due to their transgressions’. The idea that we must still pay the penalty for our transgressions contradicts 1 John 2:2.
Actually, it doesn't contradict at all. Being forgiven is different from paying for our transgressions.
Even more? OK, one more now. The necessity of confessing your sins to a priest contradicts 1 John 1:9.
No, it doesn't. Jesus told his apostles that "Whose sins you forgive are forgiven, who's sins you retain are retained." That means people had to tell them about their sins, in order to be forgiven.