The fisherman must use the cork to make sure he knows when a fish strikes his hook, the cork is used for various and sundry reasons.
In the religious world and especially in Christianity, faith is the substance of things hoped for, it is the evidence of things not seen. To him that believeth, all things are possible.
Without faith, it is impossible to please God. Faith is like a cork in the water, it rises to the top every time. You may pull it under for a moment, but it will always come back to the top and that is the thing that keeps us moving.
Who is he that overcometh the world? Of course, it is he that believeth that Jesus Christ is the Son of God. You may put a Christian down, but you can’t keep him down – he will always come back. You may silence him for a moment, but he will always come back with a stronger testimony. Persecution may arise and it may cost him, but he will reach the conclusion – we ought to serve God rather than man.
This world was not built by spineless men. It was built by men of courage who believed God would help them and that God would see them through and though the cards were stacked against them and the odds were against them, somehow, by their faith, they prevailed and went from victory unto victory.