In
Odyssey Book V, Athena complains that Calypso is keeping Odysseus against his will, so Zeus sends off
Hermes to tell Calypso to let him go. Here's the passage from a public domain translation that shows what the Swiss artist, Arnold Böcklin (1827-1901), captured in this painting:
"Calypso knew [Hermes] at once -- for the gods all know each other, no matter how far they live from one another -- but Ulysses was not within; he was on the sea-shore as usual, looking out upon the barren ocean with tears in his eyes, groaning and breaking his heart for sorrow."