The central nave of the Parish of San Andrés corresponds, as we have already seen, to the space of the primitive Romanesque temple that was later enlarged with the lateral naves. Upon entering the central nave, one notices that this is not only the tallest, but also the most decorated in the building. The rich baroque stucco of its vault, in its arches, openings, modillions and moldings show that it is a more important space than that of the lateral naves, in which only insinuated forms are insinuated.

The importance of the decoration is accentuated when entering the main chapel, where polychromy is added to the white color that characterizes the entire temple. In its vault stands out the painting of a Risen Christ that presides over and symbolically floods the entire space. In the shell of the apse the Holy Spirit is represented in the form of a dove in the midst of a luminous glory adored by the angels. This decorative richness shows us that we are in the most important place in the entire church, the one where the Christian community celebrates the Eucharist and venerates Jesus Christ present in the Tabernacle. It is therefore a space dedicated to celebration and prayer, which is therefore the heart of the church.
 

The walls of the straight presbyteral section are decorated with eight large canvases framed by baroque plasterwork. They were made by Francisco Herranz (author in turn of the Risen Christ found in the vault) in the last third of the 17th century. The cycle represented in these canvases is Christological and Mariological.
 

The themes that appear are: the Immaculate Conception, the Presentation of Mary in the Temple, the Annunciation, the Prayer in the Garden, the Flagellation, the path to Calvary and the Plain on the dead Christ. As can be seen, these are iconographies that immerse us in the mystery of Christ from the mystery of the Redemption and, also from the hand of the Virgin Mary. All this is much more than a beautiful baroque decoration. Since it helps us to remember Jesus Christ, dead and risen, precisely in the place where the memorial of his passion, death and resurrection is celebrated, he is present in the other sacraments and waits with his constant presence in the tabernacle.

The apse of the church of San Andrés presents a small axial deviation with respect to the straight presbyteral section of the main chapel. For some, this could be explained by alluding to the fact that the current central nave is not the original, but corresponds to the Mudejar reform carried out in the 13th century. However, there is another explanation according to which this deviation would not be accidental but sought, in favor of a liturgical and ecclesiological symbolism. Thus, for Santos San Cristóbal Sebastián this deviation would refer to the bowing of Christ's head when he died on the cross that the Gospel of Saint John speaks of. Following this symbolic interpretation, the nave of the Church would allude to the Body of Christ made up of the faithful who participate in the sacraments there. While the apse, where the Eucharist is celebrated, would be the head of this Body, which is Christ himself, thus following the metaphor of Saint Paul. According to this interpretation, the church as a building helps to express what the Church as a Body, of which Christ is the head, really is.