In July of this year, The Truth About Islam and Jesus (Harvest House Publishers), the third book in the Truth About Islam series, will be released.  Co-authored with world-renowned apologist John Ankerberg, this book will tackle many of the controversial issues that differentiate Christianity and Islam.  And there is no more controversial subject between the two faiths than the nature of God.  Muslims base their entire belief system on a strict monotheism in which Allah can have no partners (surah 112:3) while Christianity is based on the confession that Jesus is the "Christ, the Son of the living God" (Matthew 16:16). The question posed below, this week's blog article, tackles the crucial doctrine of God's essential character.

Is the Trinity an Unreasonable Doctrine?

Foundational to Christianity is the belief in the Triune nature of God.  From the inception of Christianity, Christians have defended the belief of One God (Deut. 6:4) in Three Persons (Matthew 28:19-20).  Indeed, any denial of the Trinity is a rejection of God's character and compromises every crucial doctrine within the Christian faith.  Millard Erickson, a premier contemporary Evangelical scholar, explains the uniqueness of Christian beliefs in comparison to other faiths:

Christianity also has been emphatically monotheistic, creating a barrier to positive relationships with other religions.  Here the thrust of the argument is not that its monotheism conflicts with the polytheism of other religions.  Rather, its monotheism prevents it from absorbing other religions, since it either must reject their god(s) or accept the other god as being the same as its God (which it does, in the case of Judaism).  Christianity cannot, without modifying its basic character, accept gods of other religions as different than its God and yet valid.ⁱ

Thus, the uniqueness of the Trinity when adhered to devoutly prevents believers from falling into idolatry and losing the very essence of who they are as Christians.  Knowing who God is allows us to know who we are called to be in Him. 

Yet, Islam believes that acceptance of the Trinity is not only unforgiveable if not recanted (surah 4:116) and irrational (surah 4:171).  But is the latter truly the case?  Is the doctrine of the Trinity unreasonable, a doctrine that is without merit and accepted blindly?  Many Christians, neglecting their own theological growth and given little sparse discipleship by their churches, are incapable of discussing God's triune character.  Some well-intentioned pastors exacerbate the problem by proclaiming the doctrine of the Trinity inexplicable.  But while it is true we cannot fully grasp it, it is entirely false to assume that someone cannot understand who God has revealed Himself to be in His Word so we may worship Him and serve Him with all of who we are.   To deny that we can understand His character is to deny His revelation of Himself.

Although many Christians are very wary at broaching the subject of God's triune character with a Muslim, a basic explanation may help.   With a Muslim, a Christian should pose two simple questions:

• 1) Is God sovereign?
• 2) Can God become Man?

According the Qur'an, God is sovereign in all his ways (surah 59:23; 2:255) and can do whatever he pleases.  It then seems to follow that he could choose to become man.  At the least, the doctrines of the incarnation and the divinity of Christ are plausible and reasonable if one accepts God's sovereignty.

However, Muslims find themselves in a quandary here.  If they answer yes to question one and no to question two, then they deny the sovereignty of God.  If they answer yes to both questions, they then fall into the most grievous sin known to Islam, shirk  - partnering anything or anyone with Allah   It would be an utter rejection of their confession that "there is no god but Allah."

In the end, it seems Islam, not Christianity, finds itself caught in an irrational belief... for it accepts Allah's complete, sovereign power but then denies even the remotest possibility that he may become whatever he chooses.

ⁱ Millard Erickson, God in Three Persons: A Contemporary Interpretation of the Trinity  (Grand Rapids: Baker Books, 1995), 18.