"Ere the bonnie boat was won as we sailed into the mystic"

"Let your soul and spirit fly into the mystic"

"And magnificently we will flow into the mystic"

"And together we will flow into the mystic"

"And when that fog horn blows I will be coming home

And when the fog horn blows I want to hear it

I don't have to fear it"

These lines repeat to emphasize that he is sailing into the mystic. Also to create a song like sound

This verse repeats to show that when the horn blows he will come home.

Repetition.