Derived from a lost Leonardo painting of the Angel of the Annunciation, St. John proclaims the arrival of Christ directly to the spectator, exuding an air of cosmic mystery in this small painting.

The atmospheric mood of the work is largely due to the impressive use of sfumato, or “smoky” effect, achieved by Leonardo through technical experiment and the scientific study of light and shade during the final years of his career. By applying layers of thin translucent varnish, the artist created a wide range of shadows, blurring the contours into soft transitions between light and shade to achieve an unprecedented plasticity in the figure.

St. John appears to be illuminated by an unknown light source outside the painting, as gentle shadows imbue his skin with a soft and delicate appearance. As God’s witness, the painting gives visual form to the first verses of St. John’s Gospel, which describe the one who was sent to bear witness to the “light that shineth in the darkness”.