This is the question

Catholic's and Jehovahs Witnesses What About Trinity “Proof Texts”?
THE New Catholic Encyclopedia offers three such “proof texts” but also admits: “The doctrine of the Holy Trinity is not taught in the O[ld] T[estament]. In the N[ew] T[estament] the oldest evidence is in the Pauline epistles, especially 2 Cor 13.13 [verse 14 in some Bibles], and 1 Cor 12.4-6. In the Gospels evidence of the Trinity is found explicitly only in the baptismal formula of Mt 28.19.”
In those verses the three “persons” are listed as follows in The New Jerusalem Bible. Second Corinthians 13:13 (14) puts the three together in this way: “The grace of the Lord Jesus Christ, the love of God and the fellowship of the Holy Spirit be with you all.” First Corinthians 12:4-6 says: “There are many different gifts, but it is always the same Spirit; there are many different ways of serving, but it is always the same Lord. There are many different forms of activity, but in everybody it is the same God who is at work in them all.” And Matthew 28:19 reads: “Go, therefore, make disciples of all nations; baptise them in the name of the Father and of the Son and of the Holy Spirit.”
Do those verses say that God, Christ, and the holy spirit constitute a Trinitarian Godhead, that the three are equal in substance, power, and eternity?