Thomas Boston, Works, 5:9 (The Art of Man-Fishing):
As the water is the natural element of fish, so sin is the proper and natural element for an unconverted soul. Take the fish out of the water, it cannot live; and take from a natural man his idols, he is ready to say with Micah, Ye have taken away my gods, and what have I more? The young man in the gospel could not be persuaded to seek after treasure in heaven, and lay by the world. It is in sin that the only delight of natural men is; but in holiness they have no more delight than a fish upon the earth, or a sow in a palace. Oh, the woeful case of a natural man! Bless the Lord, O my soul, that when that was thy element as well as that of others, yet Christ took thee in his net, held thee, and would not let thee go, and put another principle in thee, so that now it is heavy for thee to wade, far more to swim in these waters.
Source: http://www.puritanboard.com/f25/christ-took-thee-his-net-84272/, Comment #1