It stands out as Piero`s first important commission during this period. The painting was originally painted for the San Giovanni Chapel in the Pieve. The dating of this piece to Piero Della Francesca's career is evidenced by the significant relationship with the somehow light painting of his foreman, Domenico Veneziano. It is currently in the National Gallery, London. The Baptism of Christ portrays John baptising Christ, his head crowned by a dove that represents the Holy Spirit. The dove is foreshortened into a shape like the clouds. Christ, the bird, the bowl and John's hand form an axis that divides the painting into two equal parts. A second partitioning is formed by the tree standing on the left, which divides the painting following the golden ratio rule.
Behind John, there is a man in white pants. The man's feet are already in the water, and he is trying to take off his undershirt. There are three angels to the left of the panel. They wear different clothes and, as opposed to the traditional iconography, they are not holding Christ's garments. The angels are holding each other's hands instead. This could be an imitation of the contemporary Council of Florence whose aim was to unify the Eastern and Western Churches. The theologian, Saint Ambrose Traversari and Camaldolese monk, were strong supporters of the union. This kind of symbolism is also shown by the presence of images, behind the neophyte the right of the panel, dressed in oriental fashion.
The most prominent feature of the Baptism of Christ is its extraordinary lighting from the top. The lighting brings out delicate pastel colours, with the pale shadows surrounding the figures, enhancing their three-dimensionality. Piero achieved all these using the egg on poplar painting technique. The technique involved the use of a permanent painting medium which would dry fast. The painting medium usually contained coloured pigments, which Piero Della Francesca artistically used to portray the Baptism of Christ.