From this it would appear that it is part of being Father that they come from Him, all along, in other words none including the Father can exist without the others.
(No person of any kind needs to become an extra person to have a relationship with himself, it is already inherent. Sometimes, if we human beings have an under-grown personality, it can look like a very deliberate process to “acquire” this relationship! To be a person of any kind is to not be truly destined to isolation, the potential to relate is emphatically present however much - for some humans - apparently negated.)
The number three is representative. (There is also an extremely rich language of numbers in the Bible.)
The Bible isn’t meant to be taken
literally literally (note the care with which that is said).
By helping Mike with this he needn’t have been “backed” into a “corner” affording a “convenient cause” of attack by some.
In three, there is room for the
other other.
Hence, there may be a sense in which we don’t “need” “more than three”.
Jesus said that when He ascends to His Father, He will send another Paraclete-Comforter-Advocate.
Being giving from before ever, He creates, a form of giving. From His creation come His adopted sons and daughters (productive and responsible heirs in His profitable business of nurturing others’ gifts) and His Bride (as in the last 21 verses of Proverbs).
They are not exactly navel-gazers.
Also, Abraham saw three men. (Off the cuff I’m not sure why only two went off
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)