A white-bearded man in vivid red robes sits at a table, his left hand resting on the open pages of a large book while his right hand points to a passage within it. His gaze is direct and intense, set beneath furrowed brows and framed by a long, flowing beard that catches the light against the deep shadow behind him. The folds of his crimson garment are rendered in sweeping, energetic brushstrokes, with highlights of white on the sleeves and buttons that catch the light, creating a striking contrast against the dark, almost black background.

The table in front of him is covered with a green cloth, and the thick, cream-colored pages of the book are carefully detailed, showing blocks of text and the subtle shadow of his hand across the paper. No other objects or figures intrude upon the composition, focusing all attention on the solitary figure and his scholarly pursuit. The upper left and right corners of the painting are filled with a deep, uninterrupted black, with no visible objects or architectural features emerging from the darkness.

The edge of the table is sharply defined in the lower right, with a yellow-green border that contrasts with the red of the robes and the pale book pages. The light falls most strongly on the man's forehead, nose, and the upper part of his beard, creating a dramatic highlight that fades into shadow along his cheeks and jaw. The brushwork in the background is smooth and uniform, while the lines of the robe are more energetic and textured, especially along the folds at the shoulders and sleeves. The painting’s composition is tightly focused, with the saint’s upper body filling the canvas and the background receding into darkness, a device that heightens the sense of introspection and spiritual gravity.