“Go ye therefore, and teach all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Ghost” (Matthew 28:19).
This verse is the foundation of trinity teaching. It would appear to refer to God as consisting of three persons, Father, Son, and Holy Ghost. So let’s look at the command and how it was obeyed.
“Then Peter said unto them, Repent, and be baptized every one of you in the name of Jesus Christ for the remission of sins, and ye shall receive the gift of the Holy Ghost” (Acts 2:38).
It would seem, at first glance, that Peter misunderstood what Jesus told the disciples to do. But, look at Jesus’ command to baptize. He said to baptize in a name (singular). So what is the name of the Father, and the Holy Ghost? (We already know that the name of the Son is Jesus).
"For unto us a child is born, unto us a son is given: and the government shall be upon his shoulder: and his name shall be called Wonderful, Counsellor, The mighty God, the everlasting Father, The Prince of Peace” (Isaiah 9:6).
“I am come in my Father’s name, and ye receive me not” (John 5:43).
“Philip saith unto him, Lord, shew us the Father, and it sufficeth us. Jesus saith unto him, Have I been so long time with you , and yet hast thou not known me, Philip? he that hath seen me hath seen the father; and how sayest thou then, Shew us the Father? (John 14:8,9).
Since Jehovah is one of the Father’s names, and Jesus came in that name (Jehovah is salvation), the Father’s name must be Jesus. Since Isaiah said that the Son who would be given, would be called “The everlasting Father”, Jesus must be the Father, for surely He is the Son that was given. Jesus told Philip that He was the Father. We can easily determine that the name of the Father is Jesus. But, what is the name of the Holy Ghost?
"Even the Spirit of truth; whom the world cannot receive, because it seeth him not, neither knoweth him: but ye know him; for he dwelleth with you, and shall be in you. I will not leave you comfortless: I will come to you” (John 14:17,18).
“But ye are not in the flesh, but in the Spirit, if so be that the Spirit of God dwell in you. Now if any man have not the Spirit of Christ, he is none of his” (Romans 8:9).
“Now the Lord is that Spirit; and where the Spirit of the Lord is, there is liberty” (II Corinthians 3:17).
“To whom God would make known what is the riches of the glory of this mystery among the Gentiles; which is Christ in you, the hope of glory” (Colossians 1:27).
“Searching what, or what manner of time the Spirit of Christ which was in them did signify, when it testified beforehand the sufferings of Christ, and the glory that should follow” (I Peter 1:11).
Can there be any doubt that the Spirit that dwells in us, which we call the Holy Ghost, is Jesus? He said He would come to us. It says it is Christ in us. Jesus is that Spirit. In II Peter 1:21,22 it says that the Old Testament writers were moved by the Holy Ghost, yet, the Bible says that it was the Spirit of Christ. So, we know that the name of the Holy Ghost is Jesus.
All the fullness of the Godhead is in Jesus (Col. 2:9). One God, manifested in three offices. He was the Father in creation, the Son in redemption, and the Holy Ghost in habitation.