Luke 5:1-5 (KJV)
1 And it came to pass, that, as the people pressed upon him to hear the word of God, he stood by the lake of Gennesaret,
2 And saw two ships standing by the lake: but the fishermen were gone out of them, and were washing their nets.
3 And he entered into one of the ships, which was Simon's, and prayed him that he would thrust out a little from the land. And he sat down, and taught the people out of the ship.
4 Now when he had left speaking, he said unto Simon, Launch out into the deep, and let down your nets for a draught.
5 And Simon answering said unto him, Master, we have toiled all the night, and have taken nothing: nevertheless at thy word I will let down the net.
Professional fishermen spent more time washing their nets than they did actual fishing, because you can't catch fish with a nasty net. The net is an extension of our lives and there is a blessing awaiting those with a clean net, doing as the Lord commands.