Trinity Dome.

"O eternal Trinity, O Divinity, O unfathomable abyss, O deepest sea, what greater gift could Thou givest me then Thy very Self? Thou art a fire that burns eternally yet never consumed, a fire that consumes with Thy heat my self-love. Again and again Thou art the fire who taketh away all cold heartedness and illuminateth the mind by Thy light, the light with which Thou hast made me to know Thy truth. By this mirrored light I know Thou are the highest good, a good above all good, a fortunate good, an incomprehensible good, an unmeasurable good, a beauty above all beauty, a wisdom above all wisdom, for Thou art wisdom itself, the the food of angels, the fire of love that Thou givest to man. Thou art the garment covering our nakedness. Thou feedest our family with Thy sweetness, a sweetness Thou art from which there is no trace of bitterness. O Eternal Trinity! Amen." – St Catherine of Siena. Detail from the Trinity Dome in the Basilica of the National Shrine of the Immaculate Conception in Washington DC.

Source: Lawrence OP on Flickr