There are many passages in the Bible that show that the Father, the Son, and the Holy Spirit are persons distinct from one another. So also are there many passages which show that each is God. In Scripture they all share the same attributes, are involved in the same works, take council together, share the same Devine Names, and are worshiped. Father, Son, and Holy Spirit are Bible names given to each of the persons as distinct from one and other. A father has a distinct meaning as opposed to a son, and because “holy” means separated and “spirit” means breath, a separated breath has a distinct meaning from breathers (father and son). The idea of progenitor is unique to father. The idea of begotten (generated) is unique to son. The idea separation by breathing is unique to the separated spirit. Separation and begotten are terms that not only show a distinct state, but also point to a manor of origin for that state. To the Father belong the notions or ideas of generator begetter, generator breather, and as distinct from the others un-begotten and un-breathed. To the Son belong the notions of separation from the father by generation, breather of the separated breath, and as distinct from the others begotten yet un-breathed. To the Holy Spirit belong the ideas of separation by aspiration from the Father through the Son and as distinct from the others breathed yet un-begotten.
God, as Father, Son, and Holy Spirit, has no beginning in time which is a created property of the physical universe. Rather these triune relationships are eternal and simply are what God, the one and only God, is eternally as I am that I am without beginning or end. Father has no distinct meaning without progeny; thus son, though begotten of the father, is never-the-less, as equally eternal as father. A breath, furthermore, implies a breather, thus making separated breath as essential for the breathers as father is to son and son is to father. There is no time or situation when father, son, or separated breath could not all simultaneously exist and still the terms have meaning. All these terms presuppose the others in order to have their unique meanings. This is why God gives them to us in the Bible in revelation of his Tri-personal being.
The Bible is also abundantly clear that there is only one God, not three gods and that each person is the one God. Each person is not a fraction of God, but all God. The Father is all God; the only things he is not are the Son and Holy Spirit. The Son is all God; the only things he is not are the Father and Holy Spirit. The Holy Spirit is all God; the only things he is not are the Father and the Son. This is no contradiction, for the Bible does not say one person existing in three persons or one god existing in three gods, but three Persons in one God and one God in three Persons. Logically, triune-persons are thus distinguished from essential substance.
Mankind understands persons because we are one. Made in His image we are persons. Our ego or self is an indivisible whole, it is our essential substance. We have, however a physical body, a rational moral soul, and a spirit. Our one person is not divided up into these properties; it exists wholly simultaneously in these properties. The Holy Spirit bears witness with my spirit, and I Know God. I say something dumb, and I know embarrassment. I hit my thumbnail with a hammer, and I know bodily pain. I exist simultaneously without division in each property; it is the one self, person, knowing each time. This is not a contradiction, for man is not one in the same way he is three nor three in the same way he is one. There is a distinction between essential self and triune-substances.
To conclude, the Bible uses terms for three persons who are each the one God. The terms are descriptive of personal relationships that define the uniqueness of each person in such a way that they must simultaneously exist in personal relation to each of the others in order to be what they are. God is one essential substance existing without division in three distinct persons, showing us there is a distinction between person and substance. We see this again in man. But man is one essential person existing without division in three distinct substances. If we can distinguish between person and substance, and count to three, then there ought to be no problem with the notion of Trinity, accept unbelief to begin with. View this as a simple meditation upon the three words used in the Bible to name the three persons that God is. The simpler it is thought through the more obvious trinity becomes. Bless you. …DGB