This work was painted for the high altar of the Oratory of the Conception, Ferrara (attached to the church of S. Francesco) and was probably commissioned by Carlo and Camillo Strozzi. It was begun by Gianfrancesco Maineri who is responsible for the highly ornamental throne and for the smaller narratives. It was finished by Costa, probably in Maineri's absence, who revised the large figures but only modified the soldier saint (who is probably Saint William) slightly. A lunette of the Pietà (Ferrara, private collection) has been associated with it.
Narratives generally shown on the lower edge of a large altarpiece, or 'predella', are here represented on the plinth of the throne. Unusually, they read from right to left, beginning with the Nativity and concluding with Christ among the Doctors.
The Virgin was identified as the second Eve, through whom mankind would be saved, which is symbolised by the presence of Adam and Eve below her feet.
The paintings beside the arch show the Sacrifice of Isaac and probably Esther before Ahaseurus. These Old Testament episodes were believed to foreshadow Christ's sacrifice and the exceptional purity of the Virgin.