What is length? It space. What is width? It is space. What is depth? It is space.
So what is space? Space is not just length, nor just width, nor just depth. Space is all three together, each dimension distinct but inseparable.
Now let’s go to the Triune God. What is the Father? He is God. What is the Son (Jesus)? He is God. What is the Holy Spirit? He is God.
So who is God? God is not just the Father, nor just the Son, not just the Holy Spirit. God is all three together, each person distinct but inseparable.
Just as for physical space where 1 metre x 1 metre x 1 metre = 1 cubic metre (not 1 + 1 + 1 = 3), the three persons of the Trinity mutiply and enhance one another – not merely add on to one another.
So if we can accept such a concept as three-dimensional space without thinking it odd or incomprehensible, why not the concept of a three-as-one God?
The Trinity: Examples in Real Life – More metaphors for the Trinity in the sciences, including the resonance concept from chemistry
The Christian Trinity in the Old Testament – God is I, Us and He – Long before the New Testament, God Himself testifies to His triune nature
Why Christians Believe Jesus is God in Three Easy Bible Passages – Jesus told us to worship God, yet allowed people to worship Jesus