Self-Portrait open-mouthed, as if shouting: Bust

This intriguing self-portrait is one of the tronies, small facial sketches, which Rembrandt created using himself and others as models around 1630. It is very clearly a study in how to convey a certain facial expression or emotional state, in this case anguish or fury. As Erik Hinterding observed, the harsh lateral light accentuates his furrowed brow and open mouth (Hinterding, 2008, no. 7, p. 50-51). The wild hair and forward-thrust head and chin further heighten the irritation, even aggression, the figure projects.
This print presumably slightly precedes Rembrandt's more elaborate etching of the Beggar seated on a Bank of the same year (New Hollstein 50), in which the figure has the same expression. Although the face of the beggar is not directly copied from the present print, the artist clearly referred back to it - which explains why the beggar is usually seen as a self-portrait in disguise.
The dark spot on the bridge of his nose, which is quite fresh and prints with much burr in the present impression, appears in the third state and seems to vanish again in later impressions. As so often in Rembrandt's etchings, accidental marks like this don't disturb the image so much as add spontaneity and texture to it. Here it also fits the impression that the angry young man seems to have suffered some kind of injury or insult.