Santo Spirito in Sassia is a 16th century titular and former hospital church. Work began under Baldassare Peruzzi (1481-1536) and continued under Antonio da Sangallo the Younger (1484-1546). The façade was added under Pope Sixtus V (r. 1585-1590), perhaps to a design by Ottaviano Nonni (1536-1606), better known as il Mascherino.
Nave
The church has a single nave with five chapels to the left and four to the right.
Ceiling
The beautiful wooden ceiling was installed during the reign of Pope Paul III (r. 1534-49).
Apse
The sanctuary has a fresco cycle which has been ascribed to the Florentine painter Jacopo Zucchi (c. 1541- c. 1592). The theme is the Descent of the Holy Spirit at Pentecost. The fresco on the apse wall depicts disciples awaiting the Holy Spirit, while the fresco in the apse vault depicts Christ in Glory sending the Holy Spirit.
Tabernacle
The high altar has a beautiful 17th century gilded wooden tabernacle.