One way to know a work of art is iconic is to see how many other artists pay homage to it. Norman Rockwell's 1960 cover illustration for the Saturday Evening Post was instantly iconic and beloved for its brilliant composition, depth, and humor, and became one of the most famous self-portraits in art history. But Rockwell went several steps further, making it a Triple Self-Portrait. It has been homaged many times over the decades since, including this brilliant 2007 cover of Moon Knight #15 by Arthur Suydam.
What makes this more than a simple homage is the Moon Knight symbolism behind the triple-self portrait. The painter (Steven Grant) suffers from Dissociative Identity Disorder, or multiple personalities, so he is painting different aspects of himself. Even Rockwell was doing this in his portrait, looking at his reflection through fogged glasses and painting an idealized version of himself. Grant is painting at least two versions of himself, if not more if you include the small rough sketches pinned to the upper left of his canvas. The unseen painter who created this triple-self portrait (if we pretend is wasn't Mr. Suydam) may even be considered another personality. The horrific skull in the mirror is assumed to be Khonshu, the moon god who haunts and drives his avatar Moon Knight, but may be yet another personality.
Where Rockwell attached other famous self-portraits to the right side of his canvas for reference, Grant chooses formal portraits of other Marvel heroes and villains. Rockwell's heroic helmet atop his easel is replaced with Captain America's helmet/hood, perhaps implying this is who Grant aspires to be. It could also merely be a reference to Suydam's iconic cover of Marvel Zombies #2 (of 6) published in the same year as this cover.