In the middle of a terrible and frightening situation, when the ship has been blown off-course and is surrounded by fog and massive, creaking icebergs that are mast-high, the albatross is the first living thing that the sailors see in their new environment near the South Pole. Birds, of course, usually mean that land is somewhere near, and so are greeted particularly warmly, but especially for the sailors who have been at sea during an ice storm, the albatross is greeted with open arms.
Key to note is the distinctly religious way that it is introduced. The albatross "crosses" the ship and is described as if it were a "Christian soul." The albatross seems to bring the sailors good luck, as after its arrival the helmsman "steers us through" and a good south wind gives the ship the motion it needs to continue on its journey. The albatross thus becomes a firm favourite of the sailors:
And a good south wind sprung up behind;
The Albatross did follow,
And every day, for food or play,
Come to the mariner's hello!
In mist or cloud, on mast or shroud,
It perched for vespers nine;
Whiles all the night, through fog-smoke white,
Glimmered the white Moonshine.
Note how the Albatross becomes a firm fixture of life on the ship. He always joins the crew for their evening prayers and is compared to "white Moonshine," clearly referring to the luck that the sailors believe it brings them.