The ship mentioned in the first stanza was the pirate ship belonging to Sir Ralph the Rover.
No stir in the air, no stir in the sea,
The Ship was still as she could be;
Her sails from heaven received no motion,
Her keel was steady in the ocean.
The poem Inchcape Rock, tells a story of a resourceful Abbot who installed a bell on the Inchcape Rock, a dangerous reef off the coast, in order to warn sailors about the looming danger especially when the creek was submerged under the rising water. The bell was hung on a buoy that would remain afloat and ring when the creek was submerged. However, the wicked pirate decided to destroy the bell so the next sailor passing along would crash into the rock. This also implied that the pirate was spiteful towards the Abbots work and the ability of other sailors to journey safely.
His eye was on the Inchcape Float;
Quoth he, “My men, put out the boat,
And row me to the Inchcape Rock,
And I’ll plague the Abbot of Aberbrothok.”
In a turn of events, the pirate passed along the same way but due to bad weather the creek was not visible. Since he had earlier destroyed the bell, he received no warning and his ship crashed leading to his death and the loss of his entire loot.