I used to struggle with the doctrine of the Trinity because of a feeling of arbitrariness – why 3? If God has existed from eternity past in a plurality of persons, why not 30 persons in the Godhead, or 300? How can what is most basic and before all else be one thing and not another?
But recently it popped into my head: why 1, either? I had been thinking of a uni-personal God as the “normal” way for God to be, and a tri-personal God as an aberration from that. But why is 1 more “normal” than 3 in 1? Why is strict unity more basic than complex unity? Why should infinite things be like we expect them, when all we have ever known are finite things? Why should I have any notion of what God should be like to begin with?
It is comforting that God is different from what I ever could have guessed. If He were never difficult or surprising, He would not be God.