I ran across the following passage from the Office of Readings for Thursday of the Seventh Week in Ordinary Time written by St. Columban, Abbot (Instr. 1 de Fide, 3-5: Opera, Dublin, 1957, pp. 62-66). The passage is particularly fitting for Solemnity of the Most Holy Trinity.
Who then is God? He is Father, Son and Holy Spirit, one God. Do not look for any further answers concerning God. Those who want to understand the unfathomable depths of God must first consider the world of nature. Knowledge of the Trinity is rightly compared with the depth of the sea. Wisdom asks: Who will find out what is so very deep? As the depths of the sea are invisible to human sight, so the Godhead of the Trinity is found to be beyond the grasp of human understanding. If any one, I say, wants to know what he should believe he must not imagine that he understands better through speech than through belief; the knowledge of God that he seeks will be all the further off than it was before.
Seek then the highest wisdom, not by arguments in words but by the perfection of your life, not by speech but by the faith that comes from simplicity of heart, not from the learned speculations of the unrighteous. If you search by means of discussions for the God who cannot be defined in words, he will depart further from you than he was before. If you search for him by faith, wisdom will stand where wisdom lives, at the gates. Where wisdom is, wisdom will be seen, at least in part. But wisdom is also to some extent truly attained when the invisible God is the object of faith, in a way beyond our understanding, for we must believe in God, invisible as he is, though he is partially seen by a heart that is pure.
May God bless you.