This painting shows a gentleman of about 30 years of age dressed in 16 century fashion.
He wears black, but the ornament around his neck, called a ruff, and the cuff at the end of the sleeve are white.
Greco used white to highlight the face and hand of the portrayed man.
The ruff, cuff, hilt of the sword and chain with a large medal, half covered by the clothes, contrast with the overall dark colour.
The portrayed man has a serious facial expression and a reflective gaze.
El Greco often painted this facial expression on the figures in his paintings to create a religious atmosphere.
There were many debates about who this gentleman really is.
Some experts believed it was a self-portrait of Greco, others thought it was the writer and poet Miguel de Cervantes, and others believed it was Antonio Pérez, the secretary of King Philip the Second.
The idea that seems most accurate is that this gentleman is Juan de Silva y de Ribera, the third Marquis of Montemayor.
King Philip the Second appointed him warden or military commander of the Alcázar of Toledo and Chief Notary to the Crown.
The marquis remained in these posts until his death.
It is possible that he put his hand on his chest to take an oath for the post of warden.
This position of the hand was common in religious paintings but is uncommon in portraits of non-religious figures.