The founders of the church perfectly complemented the archaized architectural program with altars which are carved in wood and decorated with colorful Romanesque mosaic. The altars contain typical statues made of polychrome mass, manufactured by the Daprato Studios.
The multi-colored stained-glass windows show scenes from the life of Christ, as well as the figures of saints, including the patron saints of Poland.
The decoration of the church was completed in 1950-1951 by John A. Mallin. In the chancel and in the main nave, on a background imitating a mosaic made of golden tesserae, he painted figures of angels in the clouds. Some of them hold the arma Christi, understood here as signs of victory, while others play music reminiscent of the heavenly liturgy, the reflection of which is the one celebrated on earth.