The Three are distinct persons

12 “Listen to me, O Jacob, and Israel, whom I called! I am he; I am the first, and I am the last. 13 My hand laid the foundation of the earth, and my right hand spread out the heavens; when I call to them, they stand forth together. 14 “Assemble, all of you, and listen!  Who among them has declared these things? The Lord loves him; he shall perform his purpose on Babylon, and his arm shall be against the Chaldeans.15 I, even I, have spoken and called him; I have brought him, and he will prosper in his way.16 Draw near to me, hear this: from the beginning I have not spoken in secret, from the time it came to be I have been there. And now the Lord God has sent me, and his Spirit.

• Here we must begin by pointing out that it is YHWH speaking. The creator and eternal one. But as we read on with the continuation of speech we see something that may come as an oddity, "Draw near to me, hear this: from the beginning I have not spoken in secret, from the time it came to be I have been there. And now the Lord God has sent me, and his Spirit." Here we must emphasize, and point out the trinitarian persons of God. Since the one speaking then says, "the Lord God has sent me" and also, "with his Spirit". So then in we may read God, is sending God, with God's divine Spirit.

• We must also be careful to note, that not only are there three persons in the speech, but that they are all divine and singular. For He "the Lord begins by saying, "listen to me" He then gives a specific divine name (which Jesus also claims in Rev 1:17-18), Then He says "I have called "Him"", but then with same narration then says, "the Lord God has sent "Me" and also, not only "Him", but "and his Spirit". So then we may note not only three distinct persons, but a unified narrative voice, and since such voice at opening claims to be the eternal God the latter must also hold to such a claim since the narrative voice does not change.

16 And when Jesus was baptized, immediately he went up from the water, and behold, the heavens were opened to him, and he saw the Spirit of God descending like a dove and coming to rest on him; 17 and behold, a voice from heaven said, “This is my beloved Son, with whom I am well pleased.” 

• Here let us not possibly the most explicit passage of the three persons. The Son being baptized, the Spirit of God descending and the Father stating "This is my beloved Son".

• This also likewise establishes two things: Firstly that God is not Modalistic, since the three persons can be clearly differentiated by three distinct locations and persons, along with with three distinct actions. And secondly that the Son was not adopted to become the Father's Son, for the Father says "This Is my beloved Son", not "you have now become my Son".

16 And I will ask the Father, and he will give you another Helper, to be with you forever, 17 even the Spirit of truth, whom the world cannot receive, because it neither sees him nor knows him. You know him, for he dwells with you and will be in you. 

• Here we may also observe the three persons The Father, the Son and the Spirit.

• We may also note the distinct roles of each person or the okonomia (economic roles) of the Trinitarian persons. For here the Father grants and gives, the Son asks and intercedes, and the Spirit who dwells and also teaches truth, and "helps" or "comforts"

• Also you may note the spirit is referred to as "him" twice and "he" once

• else where the Jesus' economic role is differentiated such as, 1 Tim 2:5, Heb ( 7:25, 8:6, 9:15 ), Rom 8:34, and Jhn ( 14:13, 15:16, 15:26, 16:7, 16:23-27 ). As well as the Spirit's, Jhn ( 3:5-6, 14:26, 16:8 ) Titu 3:5, Rom ( 8:14-16, 8:26-27), Gal 5:22-23, 1 Cor12:7, 2 Cor 3:18, Acts 1:8

• Such distinct roles are not separate, but unified in achieving the same goal in the mind of God

4 There is one body and one Spirit—just as you were called to the one hope that belongs to your call— 5 one Lord, one faith, one baptism, 6 one God and Father of all, who is over all and through all and in all. 

• Here we must not all three distinct persons once more. Not only that, but once more the distinct roles of each. For the Spirit indwells the "body", we are called into the hope and faith in the Son (as well as into his baptism) and also adopted into the household of the Father, whom we now call our Father.

• One may note the text says "one God and Father", but this also refers to his distinct role in the economia of the Trinity as the Father being the Monarchia (the Monarch) in His role. This also does not disprove the other person's divinity since we have established them previously, but the distinct role and person of the Father and the one essence of God.

1Peter, an apostle of Jesus Christ, To those who are elect exiles of the Dispersion in Pontus, Galatia, Cappadocia, Asia, and Bithynia, 2 according to the foreknowledge of God the Father, in the sanctification of the Spirit, for obedience to Jesus Christ and for sprinkling with his blood: May grace and peace be multiplied to you.

• Here the scriptures once again show the unified, but unique roles of the Trinity. For the Father elects, the Son sheds and sprinkles his blood and the Spirit sanctifies us for obedience. The three although unified are strictly differentiated as to not being Modalistic (which denies distinction) and also Tritheism (which denies unity). For here we see one divine essence expressed through three distinct Persons, each active in the work of salvation—Father, Son, and Holy Spirit—perfectly harmonized in will and nature.