One of the 24 rules of correct Bible interpretation is called the ‘rule of necessary inference’. Some things in the Bible are not directly stated in the words we might wish or choose to use to express the truth it reveals, but by necessary inference, we can legitimately derive such truths from what is said.
Careful study of Scripture demonstrates that all three (and only these three and no others), that is Father, Son, and Holy Spirit are persons of the Godhead, who are associated on an equality of being, and possess the attributes and prerogatives of Deity.
Consider these facts stated in the Bible:
The Father, Son, and Holy Spirit (or Holy Ghost, KJV) are each called God.
1.1. The Father is called God:
“Is this how you repay the Lord, you foolish and senseless people? Isn’t He your Father and Creator? Didn’t He make you and sustain you? Remember the days of old; consider the years long past. Ask your father, and he will tell you, your elders, and they will teach you.”
(Deuteronomy 32:6-7)
“Yet You are our Father, even though Abraham does not know us and Israel doesn’t recognize us. You, Yahweh, are our Father; from ancient times, Your name is our Redeemer.” (Isaiah 63:16)
“Don’t work for the food that perishes but for the food that lasts for eternal life, which the Son of Man will give you, because God the Father has set His seal of approval on Him.” (John 6:27)
[See also: Galatians 1:1, 3; Ephesians 6:23; Philippians 2:11; Colossians 2:2; 1 Thessalonians 1:1; 2 Timothy 1:2; Titus 1:4; 2 Peter 1:17; Jude 1:1. These are some of the very passages that Muslims often cite when claiming Jesus is not God.]
1.2. The Son is called God:
“Thomas responded to Him, “My Lord and my God! ” (John 20:28)
“In the beginning was the Word, and the Word was with God, and the Word was God.” (John 1:1)
“The Word became flesh and took up residence among us. We observed His glory, the glory as the One and Only Son from the Father, full of grace and truth.” (John 1:14)
“The ancestors are theirs, and from them, by physical descent, came the Messiah, who is God over all, praised forever. Amen.” (Romans 9:5)
“while we wait for the blessed hope and appearing of the glory of our great God and Savior, Jesus Christ.” (Titus 2:13)
“but to the Son: Your throne, God, is forever and ever, and the scepter of Your kingdom is a scepter of justice.” (Hebrews 1:8)
“Simeon Peter, a slave and an apostle of Jesus Christ: To those who have obtained a faith of equal privilege with ours through the righteousness of our God and Savior Jesus Christ.” (2 Peter 1:1)
1.3. The Holy Spirit is called God:
“Now the earth was formless and empty, darkness covered the surface of the watery depths, and the Spirit of God was hovering over the surface of the waters.” (Genesis 1:2)
“Then Peter said, “Ananias, why has Satan filled your heart to lie to the Holy Spirit and keep back part of the proceeds from the field? Wasn’t it yours while you possessed it? And after it was sold, wasn’t it at your disposal? Why is it that you planned this thing in your heart? You have not lied to men but to God! ”
(Acts 5:3-4)
“because no prophecy ever came by the will of man; instead, men spoke from God as they were moved by the Holy Spirit.” (2 Peter 1:21)
2). The Father, Son, and Holy Spirit are each called Lord:
2.1. The Father is called Lord:
“For the Lord your God is the God of gods and Lord of Lords, the great, mighty, and awesome God, showing no partiality and taking no bribe.” (Deuteronomy 10:17)
“for there is no distinction between Jew and Greek, since the same Lord of all is rich to all who call on Him.” (Romans 10:12)
2.2. The Son is called Lord:
“Today a Savior, who is Messiah the Lord, was born for you in the city of David.” (Luke 2:11)
“Why do you call Me ‘Lord, Lord,’ and don’t do the things I say?” (Luke 6:46)
“Not everyone who says to Me, ‘Lord, Lord! ’ will enter the kingdom of heaven, but only the one who does the will of My Father in heaven.”
(Matthew 7:21)
“When Jesus had washed their feet and put on His robe, He reclined again and said to them, “Do you know what I have done for you? You call Me Teacher and Lord. This is well said, for I am. So if I, your Lord and Teacher, have washed your feet, you also ought to wash one another’s feet.” (John 13:12-14)
“For some men, who were designated for this judgment long ago, have come in by stealth; they are ungodly, turning the grace of our God into promiscuity and denying Jesus Christ, our only Master and Lord.” (Jude 1:4)
2.3. The Holy Spirit is called Lord:
“Now the Lord is the Spirit, and where the Spirit of the Lord is, there is freedom. We all, with unveiled faces, are looking as in a mirror at the glory of the Lord and are being transformed into the same image from glory to glory; this is from the Lord who is the Spirit.” (2 Corinthians 3:17-18)
3). The Father, Son, and Holy Spirit are each called or said to be everlasting:
3.1. The Father is called everlasting:
“Before the mountains were brought forth, Or ever You had formed the earth and the world, Even from everlasting to everlasting, You are God.” (Psalms 90:2)
“Have you not known? Have you not heard? The everlasting God, the Lord, The Creator of the ends of the earth, Neither faints nor is weary. His understanding is unsearchable.” (Isaiah 40:28)
“but now made manifest, and by the prophetic Scriptures made known to all nations, according to the commandment of the everlasting God, for obedience to the faith” .. (Romans 16:26)
“And He said to me, “It is done! I am the Alpha and the Omega, the Beginning and the End. I will give water as a gift to the thirsty from the spring of life.” (Revelation 21:6)
3.2. The Son is called everlasting:
“For unto us a Child is born, Unto us a Son is given; And the government will be upon His shoulder. And His name will be called Wonderful, Counselor, Mighty God, Everlasting Father, Prince of Peace.” (Isaiah 9:6)
“But you, Bethlehem Ephrathah, Though you are little among the thousands of Judah, Yet out of you shall come forth to Me The One to be Ruler in Israel, Whose goings forth are from of old, From everlasting.” (Micah 5:2)
“Jesus said to them, “Most assuredly, I say to you, before Abraham was, I AM.” (John 8:58)
“And now, O Father, glorify Me together with Yourself, with the glory which I had with You before the world was.” (John 17:5)
“Father, I desire that they also whom You gave Me may be with Me where I am, that they may behold My glory which You have given Me; for You loved Me before the foundation of the world.” (John 17:24)
“Jesus Christ is the same yesterday, today, and forever.” (Hebrews 13:8)
“When I saw Him, I fell at His feet like a dead man. He laid His right hand on me and said, “Don’t be afraid! I am the First and the Last,”
(Revelation 1:17)
“I am the Alpha and the Omega, the Beginning and the End, the First and the Last.” (Revelation 22:13)
3.3. The Holy Spirit may be said to be eternal or everlasting:
“And I will ask the Father, and He will give you another Counselor to be with you forever.” (John 14:16)
“how much more will the blood of the Messiah, who through the eternal Spirit offered Himself without blemish to God, cleanse our consciences from dead works to serve the living God?” (Hebrews 9:14)
4). God the Father, as well as Jesus Christ His Son, and the Holy Spirit are each Omniscient
4.1. The Father is omniscient:
“No creature is hidden from Him, but all things are naked and exposed to the eyes of Him to whom we must give an account.” (Hebrews 4:13)
4.2. The (Risen) Son is omniscient:
“He asked him the third time, “Simon, son of John, do you love Me? ” Peter was grieved that He asked him the third time, “Do you love Me? ” He said, “Lord, You know everything! You know that I love You.” “Feed My sheep,” Jesus said.” (John 21:17)
[This is asserted or demonstrated further in a number of passages of Scripture: John 2:24-25; John 4:16; John 5:6; John 5:42; John 6:61, 64; John 11:14 (Jesus knew days before he arrived that Lazarus was dead); Matthew 17:24-27, and many more passages. At a topical level Jesus predicted His betrayal trial death and resurrection, often in chilling detail, at least 2 dozen times:
http://www.o-bible.com/BiblicalInformation/index.html#!JESUS-PREDICTS-HIS-OWN-DEATH-AND-RESURRECTION
See also this post which established that Jesus omniscient attributes overwhelmingly established His deity:
4.3. The Holy Spirit is omniscient:
“Now God has revealed these things to us by the Spirit, for the Spirit searches everything, even the depths of God.” (1 Corinthians 2:10)
CONCLUSIONS
Only God is omniscient. Since Jesus Christ is both declared and demonstrated to be omniscient, by the rule of necessary inference, Jesus Christ must be God, that is, He always has been divine, or deity, in His eternal position as God the Son.
And again since all the attributes shared as set out above are features of the Father, Son and Holy Spirit, again by the same rule we have established that God is triune.
God desires that we use our intellects to logically reason, discern and establish with the teaching of the Holy Spirit the truth of His word.
May this post help to convict sceptics, especially those that are unreasonably prejudiced against a triune God and above all may it glorify His name. Amen.