[1] In late 1950, Hopper was invited to serve as chairman of the jury for the upcoming biennial group exhibition at the Corcoran Gallery of Art, along with Lloyd Goodrich and Macgill James.

[2] Soon Jo had painted Jewels for the Madonna (Homage to Illa); Hopper began Rooms by the Sea in late September and finished it by October.

[4] Jo attached a note to the letter, telling Rehn the painting was "A queer one – could be called 'the Jumping Off Place' – we can't count on that one ever being sold – even by a wizard like you".

[5] Rooms by the Sea depicts a creative and imaginative view outside the door to Hopper's Truro studio overlooking Cape Cod Bay.

The open door shows the large, blue bay of the Atlantic Ocean, as bright sunlight enters and falls across the bottom of the wall and floor, with shadows along the top and foreground.

[8] Photographer and educator Richard Benson observes the glaring discrepancy of size, such as the missing (or large and unseen) stairs to the door and the unusual appearance of the ocean waves in relation to the room.

"Hopper has made this view of a pair of rooms as though it's through the wide-angle lens of a camera", writes Benson, "But when he comes to the sea, it's as though he used a narrow angle that makes everything big.

[11] Katharine Kuh describes the painting as "virtually abstract", in spite of Hopper's strong resistance to the term as a modern American realist.

[13] Rooms by the Sea has been described as a "formal geometric study of light and shadow", and can be viewed in the abstract tradition of artists like Andrew Wyeth and surrealists like René Magritte.

[14] Art critic Ken Johnson acknowledges that Rooms by the Sea is "borderline surrealistic", calling it one of Hopper's "strangest" works.