"The doctrine of the Trinity is a mystery but not a contradiction. It is not that God is one person and three persons; that would be a contradiction. Nor is it that God is one God and three Gods; that would be a contradiction. It is that in God three distinct (not separate) persons share one nature, substance or essence. That is a mystery because in our world we find no exact parallel to that and we cannot create it or fully comprehend how it can be. But there is no logical contradiction involved in affirming it."