All scriptural references are from the American Standard Version unless otherwise noted
The teaching of "The Trinity"
is basically the teaching of one God existing in three separate individuals. Most Christian denominations believe in some form of the Trinity though many don't quite understand what it is. Therefore, it is important to search the Scriptures to gain a clear understanding of this doctrine in easy, simple to understand terms.
The first person in the Trinity is the Father, who is identified as either Yahweh (Hebrew version) or Jehovah (Anglicized version) This can be seen in the King James Version in places such as Exodus 6:3, Psalms 83:18, Isaiah 12:2, and Isaiah 26:4. Some other Bible versions use God's name throughout the Old Testament, which you can see in American Standard Version, Darby Translation, The Living Bible, New Jerusalem Bible, and Rotherhams's Emphasized Bible.
The Father is specifically referred to as God (John 6:27, Galatians 1:1-3, Ephesians 1:2, Philippians 1:2, 2 Timothy 1:2) and as the Almighty God (Exodus 6:3, 2 Corinthians 6:18, Revelation 15:3). The Heavenly Kingdom belongs to the Father (Matthew 26:29, 6:10, 13:43, Luke 12:32). Although Scripture states that the Father gave the Son all authority, it is with the understanding that the Son's authority stops short of the Father Himself (1 Corinthians 15:27), and the Son will return all his power and authority to the Father (1 Corinthians 15:28).
The Father's absolute authority is also revealed in the fact that He is the head of Christ (1 Corinthians 11:3), and that the Father is the only One that knows when The End will be (Matthew 24:36, Mark 13:32). Scripture also tells us that all good things we receive originate with the Father (Matthew 6:26-33, James 1:17) and that God is the Father of our Lord, Jesus Christ (Ephesians 1:3).
"Jesus Christ" is the Greek form of the name, "Yeshua Messiah" is the Hebrew form of the name. Scripture tells us that Jesus Christ is the Holy Son of God (Matthew 1:20-22, Luke 1:31-32). Jesus existed in Heaven with The Father before He was born as a man on the Earth (John 1:1-18; John 3:13; John 6:33,38,62; John 8:23,58). The names “Christ” and “Messiah” both mean “The Anointed One”. Jesus Christ recognized that the Father is greater than Jesus Himself (John 14:28, 15:1), and that the Father is His teacher (John 8:26-27). Christ performed only the duties assigned to Him from the Father, and never His own duties (John 4:34, 5:19,30, 36-37, John 8:26-28, 12:49-50, 14:24, John 20:21, 1 John 4:14). Although Christ was capable of following His own will, as implied at Matthew 26:53, He remained obedient to the Father's will, even when it was very difficult (Matthew 26:39, 42). Christ always instructed people to follow the Father's will (Matthew 7:21, 12:50).
Although Christ was prophesied as being called "Mighty God" (Isaiah 9:6), He is never referred to as Almighty God; He referred to the Father as the only True God (John 17:3) as well as the only God (John 5:44), and referred to the Father as His own God as well (Matthew 27:46, John 20:17). He taught that people should worship the Father (John 4:21, 23) and pray to the Father (Matthew 6:9). Christ Himself prayed to the Father on occasion (Matthew 26:39, 42, 53). The only power that Christ has is that which is given to Him from the Father (Matthew 28:18, John 3:35, John 5:20-24). Jesus Christ is the Mediator between the Father and mankind (John 14:6, 1 Timothy 2:5, Hebrews 12:24).
THE HOLY SPIRIT
The Holy Spirit is also known as the Holy Ghost, and Scripture does not reveal whether it has a personal name. This is not unusual, for there are other spirits in Scripture who are also unnamed (1 Kings 22:21, Ezekiel 3:12). The Holy Spirit is something that is of the Father and is given from the Father (Luke 11:13, 1 Corinthians 6:19. Ephesians 4:30, 1 Thessalonians 4:8, Hebrews 2:4, 1 John 2:20) For example, it was through the power of Holy Spirit that Jesus Christ was conceived as a human baby (Matthew 1:18, 20). Later, the Father bestowed Holy Spirit upon Jesus Christ after his baptism (Luke 3:22, Acts 10:38). John the Baptist taught that believers would be baptized with Holy Spirit (Matthew 3:11). Holy Spirit was given to a group of people during Pentecost in order to spread the Gospel (Acts 2:1-17). Jesus taught that Holy Spirit would be given to Christian believers upon request (Luke 11:13) and during times of intense persecution (Matthew 10:20, Mark 13:11). Holy Spirit was also given as a means of knowledge (Luke 2:26). Sometimes it was given to bestow special abilities on believers (Acts 1:8, 19:6). Holy Spirit was given on other occasions as well (Acts 2:38, 4:31, 8:17, 10:45, etc.).
Although the Holy Spirit is personified in some cases (Acts 13:2, 21:11, Hebrews 3:7), it has never been said to act on its own behalf. Although it is said to teach (John 14:26), and to speak (Mark 13:11, Acts 1:16), it is always the Father who dispatches it (John 14:16,26 15:26, Acts 2:33, 5:32). Sometimes, the Father will dispatch the Holy Spirit in the name of Christ (John 14:26, 20:22). The Holy Spirit is spoken of as having great power (Acts 1:8, Romans 1:4, 15:13, 19).
Due to the above-mentioned Scriptures many Christians believe that the Holy Spirit is a sentient (self-aware) spirit that acts on God's every command. There are those, however, who disagree and instead believe that it is simply the impersonal power of God because the it has neither a personal name nor the free will that God has given to all other sentient creatures. Another school of thought holds that the Holy Spirit is the spiritual counterpart to a tree; a living entity that is neither sentient nor has free will, and yet can be useful to God in many ways. Personally, I am of the opinion that the Holy Spirit is a force so unique and unparalleled that humankind has nothing that our minds can relate it to; this is why it can be such a confusing thing to neatly categorize.
BLASPHEMING THE HOLY SPIRIT
According to Easton's Bible Dictionary “Blasphemy” is defined as follows:
In the sense of speaking evil of God this word is found in Ps. 74:18; Isa. 52:5; Rom. 2:24; Rev. 13:1, 6; 16:9, 11, 21. It denotes also any kind of calumny, or evil-speaking, or abuse (1 Kings 21:10; Acts 13:45; 18:6, etc.). Our Lord was accused of blasphemy when he claimed to be the Son of God (Matt. 26:65; comp. Matt. 9:3; Mark 2:7). They who deny his Messiahship blaspheme Jesus (Luke 22:65; John 10:36). Blasphemy against the Holy Ghost (Matt. 12:31, 32; Mark 3:28, 29; Luke 12:10) is regarded by some as a continued and obstinate rejection of the gospel, and hence is an unpardonable sin, simply because as long as a sinner remains in unbelief he voluntarily excludes himself from pardon. Others regard the expression as designating the sin of attributing to the power of Satan those miracles which Christ performed, or generally those works which are the result of the Spirit's agency.
Blasphemy against the Holy Spirit is the only sin that is unforgivable:
Note that, in the passage above Christ states that blaspheming the Son is forgivable – that is was only blasphemy against the Holy Spirit that was unforgivable. Since the Holy Spirit performs only according to God's command, evidently it seems that blaspheming it would be the same as blaspheming God Himself. This is why it is such a serious offense.
At Mark 3:28-29 the scribes accused Jesus of performing works through the use of evil spirits when in reality he was performing works through the Holy Spirit. By this accusation they were slandering the Holy Spirit by naming it evil; thus, Jesus made it clear that such a sin is beyond forgiveness.
ONE IN PURPOSE
Although the Father and the Son and the Holy Spirit are separate entities (Romans 1:7, 1 Corinthians 8:6, 2 Corinthians 1:2, Galatians 1:3, Ephesians 1:3), they are one in purpose (John 10:30, 16:15). This is why Jesus always did the Father's will instead of his own: The Son obeys the Father (Matthew 26:39, John 5:19, Romans 5:19, Philippians 2:8, Hebrews 5:8), is in subjection to the Father (1 Corinthians 11:3, John 20:17), and directs all attention to the Father (Matthew 5:45, 7:21, 12:50, John 4:23). It is never the other way around. Because they are one in purpose Scripture tells us that Christ is the Word (John 1:1) and that we should honour the Son as we would the Father (John 5:23). Similarly, as shown earlier, the Holy Spirit acts according to the purpose of the Father and never on its own motivation; even when it acts according to the Son's purpose, the Son is only acting according to the Father. And thus, the three are distinctly different, yet they all act in unison as one in purpose.
This can be likened to a kingdom in which the king sends his son and his daughter to issue a decree to the citizens: Even though the son and the daughter are not the actual king, they are still acting as one with the king's purpose and thus the citizens accept the message from the son and daughter as though they were accepting it directly from the king himself, and thus regard it as the king's decree and nobody else's. In like manner, the Father, the Son, and the Holy Spirit are viewed as "God" even though the Father is the one and only true God who directs the Son and the Holy Spirit.
Modalism, a.k.a. Sabellianism, is a core doctrine in the United Pentecostal Church, the United Apostolic Church, and a few others. In a nutshell this is a teaching that states the Father, the Son, and the Holy Spirit are all actually one singular entity playing an ordered succession of modes. (This is akin to an individual man playing an ordered succession of modes, for example from apprentice to professional to retiree). According to this doctrine this entity plays the Father mode in the Old Testament, the Son mode in the Gospels, and the Holy Spirit mode after Christ's ascension. This doctrine teaches that this entity plays these modes consecutively in the Bible and never plays more than one mode at a time.
I do not subscribe to the doctrine of Modalism because I believe the Bible clearly shows these to be three separate beings who exist concurrently. For example, when Jesus was baptized the Holy Spirit visibly came upon him and the Father spoke from heaven (Luke 3:21-22), clearly showing all three “modes” existing concurrently. Similarly damaging is the passage at John 12:27-28, when Jesus is in Jerusalem as the Father speaks from heaven. On other occasions Jesus Christ referred to the Father and Holy Spirit existing simultaneously (Luke 11:13),Jesus prayed directly to the Father (Luke 10:21, 22:42, 23:34), and spoke of his Father's will being distinctly different from his own (Mark 14:36, John 8:28, 12:49). It keeps going: John the Baptist was to be filled with the Holy Spirit despite Christ's simultaneous existence (Luke 1:15). The Holy Spirit was in existence when Jesus was a newborn baby (Luke 2:25-28). Jesus was filled with the Holy Spirit on certain occasions (Luke 4:1), and Jesus bestowed the Holy Spirit on his men (John 20:22). It is also interesting that, as mentioned earlier, Jesus stated that blasphemy against himself was forgivable, but not blasphemy against the Holy Spirit (Mark 3:28-29), indicating that he was a separate entity from the Holy Spirit.
It is undeniable that the Father, Son, and Holy Spirit are three separate things that exist simultaneously -- the Bible is very clear on this.
The Trinity can be described as three individual elements -- The Father, His Son, and the Holy Spirit -- that work together for one common purpose. Each has an individual role to play and each is separate from the other: The Father is primary, the Son is secondary, and the Holy Spirit is dispatched at the command of the Father and/or the Son. The Bible does not support a doctrine of Modalism, therefore it should be viewed as a false teaching.