The messenger who kneels with a lily and speaks first — the single scene that fixed how an angel should look.
Gabriel exists in painting almost entirely for one scene. He arrives at the Annunciation, usually from the left, usually kneeling or just landing, carrying a lily for the Virgin's purity and sometimes a scroll with the words of the greeting. The room he arrives in is often as carefully painted as he is: the Annunciation is where painters put their perspective, their tiled floors and their most expensive blue.
Guido Reni