7 Thus, in the eyes of God, the sea is good, because it makes the under current of moisture in the depths of the earth. It is good again, because from all sides it receives the rivers without exceeding its limits. It is good, because it is the origin and source of the waters in the air. Warmed by the rays of the sun, it escapes in vapour, is attracted into the high regions of the air, and is there cooled on account of its rising high above the refraction of the rays from the ground, and, the shade of the clouds adding to this refrigeration, it is changed into rain and fattens the earth. If people are incredulous, let them look at caldrons on the fire, which, though full of water, are often left empty because all the water is boiled and resolved into vapour. Sailors, too, boil even sea water, collecting the vapour in sponges, to quench their thirst in pressing need.
Finally the sea is good in the eyes of God, because it girdles the isles, of which it forms at the same time the rampart and the beauty, because it brings together the most distant parts of the earth, and facilitates the inter-communication of mariners. By this means it gives us the boon of general information, supplies the merchant with his wealth, and easily provides for the necessities of life, allowing the rich to export their superfluities, and blessing the poor with the supply of what they lack.
But whence do I perceive the goodness of the Ocean, as it appeared in the eyes of the Creator? If the Ocean is good and worthy of praise before God, how much more beautiful is the assembly of a Church like this, where the voices of men, of children, and of women, arise in our prayers to God mingling and resounding like the waves which beat upon the shore. This Church also enjoys a profound calm, and malicious spirits cannot trouble it with the breath of heresy. Deserve, then, the approbation of the Lord by remaining faithful to such good guidance, in our Lord Jesus Christ, to whom be glory and power for ever and ever. Amen.
Source: Nine Homilies of Hexaemeron (New Advent)