To commemorate its completion in 1188, the date was carved on a stone set in the cathedral and on the lintel that supports the richly ornamental tympanum.
[1] Under the contract made in 1168, if Mateo was to renege on the deal to create the portico at any time, he would have to pay 1,000 gold pieces (aureos).
[3][4] Originally projected as a four-part division, it was modified into a three-part format, which changed the proportions of the entire portal.
[6][7] The Pórtico de la Gloria consists of an inner double-arched porch and finished with an outer western façade.
[1] The lateral archivolts were left undecorated, which might have been due to time restraints to finish the gate for the Jubilee of 1182 and formal procession of pilgrims.
Without door valves, the three large arches were decorated with angels and foliage and framed the ciborium and altar at the end of the nave.
[5] Though the portal was originally poly-chromed, the numerous traces of the remaining paint seen today are due to later interventions.
[5] The more enamel-like painting is harsher and darker with ornamental patterns dated back to the 17th century in a similar style to offering boxes in 1656.
[5] The width of the portico was governed by the western edge of the towers and limits its view; the porch measures approximately 57 ft by 13.5 ft. Because Mateo was confined by the horizontal space, he designed upwards and higher.
[11] He used an abundance of sculpted reliefs and three round arches that correspond to the three naves of the church, supported by thick piers with pilasters.
Master Mateo was also influenced by the local tradition and sculpture of the Puerta de las Platerías and the Cámara Santa of the cathedral of Oviedo.
[8] French influence is seen in the iconography and composition with decorative sculpture similar to the details of the cloister of Santo Domingo de Silos Abbey.
[8] Style and technique are completely unique to Master Matthew and his group of masons and sculptors of varying skill level.
The left arch is decorated with sculptures of patriarchs of the Old Testament and Jewish people waiting for arrival of the Christ.
[4] The Pórtico de la Gloria operates as a highly symbolic narrative whose function is to combine the present and the individual act of pilgrimage with meaning; by inscribing them within the universal and the eternal.
[12] Mateo's figures in the Pórtico de la Gloria were the first manifestations of the Gothic spirit in European sculpture.
The trumeau statue of Santiago in the Pórtico de la Gloria, depicts a seated James, with nimbus, holding a scroll in one hand and a Tau-shaped staff in the other.
Numerous sculptures of James bear witness to the Transfiguration, like the one which the Pilgrim's Guide describes as adorning the west front of the Cathedral at Compostela in the early twelfth century as a participant in the Last Supper.
The Evangelists form a tetramorph around Christ and have emblematic animals on their knees: St. John, an eagle; St. Luke, a lamb; St. Mark, a lion; St. Matthew writes on a scroll.
The next angel holds the jar of vinegar (Gallegan jarro or water-pot) in his left hand and the scroll on which Pilate wrote Christ's sentence.
[2][9] Flowers cover the vault while angels carry and lead souls to Paradise, symbolizing the Day of Judgment and praising the lord.
[16] The portal's doorway is so broad that its lintel must be supported by a trumeau or mullion in the form of a huge composite column.
This symbol of the human genealogy of Christ is the first time that this subject is represented in religious iconography in the Iberian Peninsula.
The column rests on a base where there is a bearded figure (perhaps an image of Noah) with arms extended over two lions with open jaws.
At the foot of the central column looking towards the main altar of the cathedral, is a secular, kneeling figure of a young man with curls symbolizing Master Mateo, holding a sign that is written "Architectus" and an inscription dating the completion of the principal portal.
[8][note 2] The opposite columns on the right of the central arch are the four Apostles: Saints Peter, Paul, James and John the Evangelist.
[9] Below the southern arch on the left are the apostles Philip and Andrew followed by Bartholomew and Thomas on the right.There are three more statues on either side of the outer doors corresponding to the column figures.
[8] The arch of the left door, the northern portal, depicts scenes from the Old Testament, with an upper and lower band with the righteous awaiting the arrival of the Savior.
[6] In the center of the lower archivolt is God the Creator who blesses the pilgrims and holds the Book of Eternal Truth.
[5] The figures in dense foliage holding scrolls contain the word of God as revealed to the Jews, but are bound by heavy moldings symbolizing the Judaic Law which imprisons them.