2 Now though the mind is most rapid in its thoughts, yet the tongue needs words, and a long recital of intermediary speech. For the eye embraces at once a multitude of the 'starry quire;' but when any one wishes to describe them one by one, which is the Morning-star, and which, the Evening-star, and which each one of them, he has need of many words. In like manner again the mind in the briefest moment compasses earth and sea and all the bounds of the universe; but what it conceives in an instant, it uses many words to describe. Yet forcible as is the example I have mentioned, still it is after all weak and inadequate.
For of God we speak not all we ought (for that is known to Him only), but so much as the capacity of human nature has received, and so much as our weakness can bear. For we explain not what God is but candidly confess that we have not exact knowledge concerning Him. For in what concerns God to confess our ignorance is the best knowledge. Therefore magnify the Lord with me, and let us exalt His Name together —all of us in common, for one alone is powerless; nay rather, even if we be all united together, we shall yet not do it as we ought. I mean not you only who are here present, but even if all the nurslings of the whole Church throughout the world, both that which now is and that which shall be, should meet together, they would not be able worthily to sing the praises of their Shepherd.
Source: Catechetical Lectures (New Advent)