God the Father, God the Son, and God the Holy Spirit exist as “one.” Jesus said to His disciples, “I and my Father are one” (John 10:30). Practically and logically, this concept introduced by Christ has proven to be very difficult for people to wrap their minds around. The scriptures reflect this statement of Christ in other passages and words such as the term “Godhead,” which is used three times in the Bible (Acts 17:29; Rom. 1:20; Col. 2:9). Another word commonly associated with this concept taught by Christ is the word “Trinity;” however, the word is actually not in the Bible, but the teaching that there are three individual personalities of divine nature (known in the New Testament as the Father, the Son, and the Holy Spirit) is thoroughly scriptural (1 John 5:7,8; Gen. 1:26).
Other religions, such as Islam, Buddhism, and Hinduism, have called Christians polytheistic because of their doctrine of the Godhead. As a response to this problem, numerous denominations of the Christian world have over-compensated by teaching a Oneness heresy called “Monarchianism.” The doctrine represents God as uni-personal and that the names Father, Son, and Holy Ghost merely designate the same person in different capacities. This doctrine has even gone so far as to designate Christ as an adopted Son of God in order to maintain the “oneness” of God while Christ was on earth. Christians need to be able to address why they are not polytheistic (Eph. 4:6), how three equals one (John 10:30), and how the Godhead works in their lives 1 John 5:6-12).
The belief in one God is called monotheism, which is taught and supported through a Bible-based faith. Moses stated, “Hear, O Israel: The LORD our God is one LORD” (Deut. 6:4). The Ten Commandments required the worship of only one God, “Thou shalt have no other gods before me” (Ex. 20:3). In the Christian dispensation, Paul, the apostle, wrote to the church in Galatia, “Now a mediator is not a mediator of one, but God is one” (Gal. 3:20). Clearly the New and Old Law both taught and required the worship of one God. However, the Bible likewise taught a three-person divinity. Jesus said, “Go ye therefore, and teach all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Ghost” (Matt. 28:19). How can there be three if Christians worship only one God?
The Bible mentions personal distinctions between the three, such as the name and work (Matt. 28:19; 2 Cor. 13:14), but they are all described under the same nature – deity (God) (Eph. 1:2 [the Father]; Heb. 1:8 [the Son]; Acts 5:3,4 [the Spirit]). However, any elementary student of logic knows perfectly well that the Godhead cannot be both one and three without a logical contradiction being involved, so how does a believer make sense of the idea? When it is said, therefore, that there is but one God, the meaning is: there is but one divine nature. The fact of the matter is, they are not used in the same sense. There is but one divine nature, but there are three distinct personalities possessing that unified set of infinite qualities. Thus, there is no contradiction at all. The oneness is describing the nature of God and divinity.
How can three personalities be of a single unified deity? It is possible in the same sense that Christians are united in one mind and one judgment (1 Cor. 1:10; 12:12-18). If a person can understand how a husband and wife become “one” in mind and life (Gen. 2:24); if a person can understand how actors become ‘one’ with their characters; if a person can understand how an outdoorsman becomes ‘one’ with nature, then a person can understand how the Father, the Son, and the Holy Spirit can be one. A common illustration that this author has used to help a Muslim understand the Godhead is fire. Just as fire is one element in the world, yet it has three distinct and separate qualities: heat, light, and the physical flame itself, so is God a being one element yet of three distinct persons: Father, Son, and Holy Spirit. Heat is quite different than light, and light is very different than the flame, yet the three cannot be separated in fire, they are one element. The same could be said for the Father, the Son, and the Holy Ghost. While these examples may not be a perfect parallel to the Godhead, it certainly helps a person start thinking in the right direction.
Within mankind’s redemption, God the Father designed the plan of redemption (Eph. 1:11; Rom. 8:29), God the Son executed the plan (John 6:38; 2 Tim. 1:9), and God the Holy Spirit revealed the plan (John 14:26). Each and every person has the opportunity to be saved through the work and grace of the Godhead! Truthfully, a Christian doesn’t have to completely understand the Godhead to be obedient to the message of God. Nevertheless, to be a defender of the faith and help others be convinced of the Bible’s inerrancy and credibility, the Christian needs to have a reasonable defense for why he/she believes in the unity of the Godhead (John 14:1, 11; 17:21).