With the advent of the Diwali the sea-farers set sails. This time the (favourable) northern wind came rather suddenly. For the sea-traders the only topic for conversation was this visit to the land across the sea (the other world).
Note: (1) To pious persons the favourite topic is the Hereafter. They are not interested in the worldly affairs.
(2) Diwali is an occasion of festival for the Hindus to celebrate the victory of Siri Ram over forces of evil, his reunion with his beloved wife Sita Bai and their return to their original land. Death which bridges up the gulf of separation between the Creator and His creatures and facilitates their reunion is actually an occasion of celebration rather than lamentation. The Momins consider this world as a prison-house and they always look for release from it. For them death is Diwali.

The Dayari set in, the seafarers set sail,
This time the north wind blew in early,
The sea traders are always thinking of the other shore.