George Leo Haydock

This light of the world, city on a mountain, and candle upon a candlestick, signify the Catholic Church, so built upon Christ, the mountain, that it must be visible, and cannot be hidden or unknown. (St. Augustine, cont. Fulg.) Therefore the Church being a candle not under a bushel, but shining to all in the house, i.e. in the world, what shall I say more, saith St. Augustine than that all are blind, who shut their eyes against the candle which is set on the candlestick? (Tract ii. in ep. Jo.)