On June 9th, 2018, Mikhail Kosenkov asked the Mentionables:
Is tri-person-hood an essential attribute of God that stems from the necessity of God's own nature, and thereby, being a necessary attribute, there can be no possible world where God is not tri-personal? Or, is it logically possible for the Godhead to consist of four or more Persons? If it is logically possible for the Godhead to consist of four of more Persons, then can God wonder why He happens to be tri-personal?
Since God is the foundation of logic, it would mean that whatever he is essentially, he is necessarily. This means that Gods being a Trinity, as an essential property of God, is a necessary property of God and could not be otherwise.
This is the answer from Randy Hroziencik. For the answer from Marc Lambert and Robert Vroom, scroll below
Although the word "Trinity" is not found in Scripture - it was the Church Father Tertullian who would first use that term over a century after the NT was completed - it is nonetheless clear from the Bible that God exists in triune form, or three distinct persons who are one in essence. The scriptural case for God's triune nature is as follows:
There is one God, as clearly revealed in Scripture (Isaiah 44:6; John 5:44; 17:3; Romans 3:29-30; 1 Corinthians 8:4; Ephesians 4:4-6; 1 Timothy 2:5; James 2:19). However, there are three separate persons called God. This teaching is easily surmised through many verses such as 1 Peter 1:1-2 (God the Father), John 1:1-14 (God the Son), and Genesis 1:1-2 (God the Spirit). The Bible teaches a three-in-oneness within the Godhead in other key places as well (Matthew 3:16-17; 28:19; 2 Corinthians 13:14).
The only reason that we know of God's triune nature is because God revealed it to us, through his Word (special revelation). Although the universe (Romans 1:20) and the conscience (Romans 2:14-15), which is collectively referred to as general revelation, allows us to know that God exists and that he is beyond intelligent and powerful, it is only through his self-revelation that we can know that he exists in triune form. The Trinity is not a contradiction, but rather it is a paradox: It simply goes beyond logic and reasoning.
Normal logic and reasoning would lead us to think of God in a strict monotheistic manner, just as Jews and Muslims do: One God, in one person. So logic and reasoning would not lead us to think of God as being two persons in one essence, or three persons in one essence, or any other number of persons in one essence. If we did not have God's self-revelation in Scripture, we would never think of God as being anything other than one God in one person.
I don't think God wonders why he is triune in nature. As an omniscient being (Job 37:16; Psalm 33:13-15; 139:1-4, 15-16; 147:4-5; Isaiah 46:9-10; Matthew 10:29-30; Romans 11:33; Hebrews 4:13; 1 John 3:20) I believe that God fully understands why he is as he is. We, as limited, finite beings whose ability to employ logic and reasoning has been marred to some extent by the fall, wonder about God, but God knows all - and does not need to wonder about these deep questions of theology. That's our burden!
The Trinity is a classic case of rational fideism, which is the approach to theology and apologetics in which faith in God's revelation takes over where reasoning can go no further. Although we can reason that God exists, through the cosmological, teleological, ontological, and moral arguments, for instance, or Aquinas' "Five Ways," we cannot understand God's nature without his revealing it to us. Although natural theology has its place, it is limited and does not provide us with the much more detailed information that only God can provide us with.
Even if there were "other possible worlds," or circumstances which are dramatically different from what they are in this world (universe), God would still be God - exactly as he is now, and has always been and will always be (Malachi 3:6 & James 1:17). I believe that God would be triune in any possible world. "Other possible worlds" is an interesting idea - it comes up in a discussion of Molinism, for instance - but ultimately the only world that we can even begin to start to comprehend is this one, so it may be a theological idea that, while interesting, is too speculative to be of much benefit. It definitely stretches the mind, though!
This is the answer from Marc Lambert. For the Answer from Robert Vroom, scroll below.
The short answer is that since God has revealed to us that there are three persons in the Godhead, we have no reason to suspect that there may be more.
However, if someone merely wants to do a thought exercise just because, then there are ways to do that. My preferred method is to ask three questions to narrow down the answer. (1) Is it Possible? Anything that is not a logical contradiction is technically possible. (2) Is it Plausible? There can be all sorts of things that may technically be possible, but really don’t seem like they could sensibly be the case. (3) Is it Probable? Not everything that can be plausibly conceived is actually likely to be true. Often to figure out an answer we have to figure out the most probable explanation.
OK, so let’s look at there being more than 3 persons in the Godhead
While we are not told of any additional persons, there does not seem to be any logical contradiction in the idea that there could be. This would mean that it is possible that there could be more.
That doesn’t mean that it is plausible, however. It is possible that there is a secret empire of Lizard People living underground who are covertly infiltrating world governments. However, that just really doesn’t seem very plausible. Likewise, while there may be nothing logically contradictory about there being an unknown 4th (or more) person within the Godhead, when we look at the roles each person fulfills, it does not seem plausible to me that there would be more as there is nothing for them to do. We would have the Father, Son, Holy Spirit, and the Freeloading Houseguest. That doesn’t seem very fitting to the nature of a maximally great being. However, I could imagine that perhaps there is something else that God is engaged in in the spiritual or heavenly realm that has nothing to do with mankind or whose purpose we couldn’t fathom. So while I don't think it's very plausible, just for giggles let's say it is.
Is such a thing very probable? Here I am going to say, "No." God is a relational being. He created us to be in relationship with Him. He wants to be known. God has revealed Himself through both the general revelation of creation and the specific revelation of the Bible. Given such a focus on knowing and being known, it seems highly improbable that God would leave out such a major aspect of His nature. Indeed with the trinitarian description in the Bible, we might consider the existence of additional persons in the Godhead to be a deception on God's part. And THAT certainly would be impossible since God cannot lie.
So overall, the notion that God could be more than 3 persons is off the table as far as I'm concerned.
Regarding this last piece ... "can God wonder why He happens to be tri-personal?" ... as God is omniscient, I don't imagine He does any wondering about anything. He would know why He is Trinity and not other.
This is the answer from robert vroom
There are certain aspects of God that I as a Christian accept. Among these are the ideas that God is eternal, unchanging, and necessary. If God is eternal, there is no time at which He did not exist. If God is unchanging, He has always been exactly as He is now. If God necessary, He could not have not existed. It seems therefore that if God has these traits, He has necessarily existed eternally exactly as he is today, which includes tri-personhood.