Retrato de un hombre afilando su pluma

In 1632 Rembrandt was 25, recently arrived in Amsterdam from Leiden, and taking portrait commissions as fast as they came. It is the year of The Anatomy Lesson of Dr Tulp, and the year he changed how he signed. Until then he had used the monogram RHL, for Rembrandt Harmenszoon of Leiden. This canvas reads RHL van Rijn 1632, with the family name added, and within a year or two the monogram was gone and he was signing Rembrandt alone, the way the Italian masters had.

Trimming a fresh point onto a quill was a recognised emblem of steady application, the sort of thing a scholar or a writing master wanted to be shown doing. The man here was long identified as the Amsterdam calligrapher Lieven van Coppenol, an identification since dropped because he does not match the secure portraits of Coppenol.

Kassel holds three paintings signed and dated 1632. This one is thought to have had a companion, a woman's portrait now in Vienna.