San Blas is today a downtown neighborhood in the city known as the "Artists District", with narrow and writhing streets, most of them steep. In Inkan times it was one of the most important districts of Qosqo and its name was "T'oqo-kachi" (T'oqo = hollow; kachi = salt). Like the other districts it was inhabited by the Quechua nobility.

It seems that the church was erected over an Inkan Sanctuary devoted to cult of the "Illapa" god (Thunder, Lightning and Thunderbolt). It was possibly opened for the first time in 1544 by the city's second Bishop Juan Solano. Although some other versions say that it was after 1559 as consequence of viceroy Andres Hurtado de Mendoza's order by which "Indians" had to built churches for their indoctrination in the districts where they lived. Its structure was simple with a rectangular floor plan and mud brick walls, but after the earthquakes in 1650 and 1950 it was partially reinforced with stone walls. It has just one nave and two gates before which there are big plazas; and a stone bell tower constructed after the 1950 earthquake instead of the original made with mud bricks.

Inside the church is one of the greatest jewels of colonial art in the continent: the Pulpit of Saint Blaise; which is a filigree made in cedar wood by expert hands managing a gouge. It is not known with certainty who was the artist or artists that made it, how long the work lasted, neither any other details about it. However, the pulpit is over there as a mute witness of a great Catholic devotion and devoted work.

There are enough proofs to assert that it was made carved with funds given by art protector Bishop Manuel Mollinedo y Angulo; therefore, it was by the end of the XVII century. There are serious discrepancies about the identity of the performing artist.
Most authors suggest that it was made by the most famous Quechua woodcarver: Juan Tomas Tuyro Tupaq, that was contemporary and protected of Mollinedo y Angulo, who entrusted him the manufacture of several works. It also could have been work of some other artists contemporary with Mollinedo such as Martin de Torres, Diego Martinez de Oviedo who made the monumental High Altar of the Compañia de Jesus Church, or the Franciscan Luis Montes that made the San Francisco Church's choir. Oral tradition has its version gathered by Angel Carreño who in his "Cusquenian Traditions" manuscript had stated in writing the name Esteban Orcasitas as the pulpit's author; but, for the 1st. edition of his book the name was changed by that of Juan Tomas Tuyrutupa. Tuyrutupa was Quechua and Cusquenian, but according to that traditional version he was a leper woodcarver from Huamanga (Ayacucho). The story tells that once he had in his dreams a revelation of the "Holy Virgin of the Good Happening" who told him that if he wanted to get healed from his leprosy he had to look for her in the small plaza of Arrayanpata in Qosqo City.

After a long journey and many mishaps, one day he found her painted on a wall after that the roofing of the "Lirpuy-Phaqcha" chapel fell in. Falling on his knees and weeping he invoked her, as the Virgin's rosary became rose petals with which he rubbed hard his whole body remaining thus completely healed. The piece of wall containing the painting was cut and moved to the Saint Blaise Church, then people agreed upon to build an altarpiece and a pulpit for the Virgin..

• Martin Luther, creator of Lutheranism and chief of the religious reform in Germany;
• John Calvin, founder of Calvinism in France and Switzerland;
• Ulrich Zwingli, friend and follower of Calvin;
• Henry VIII, king of England who denied the Pope's authority and created Anglicanism;
• Elizabeth of England, who was daughter and follower of Henry VIII;
• Arius, native from Alexandria and founder of the Arianism;
• Phocion, who along with Arius made the great orthodox greeks schism or eastern schism;
• Catherine of Bora, wife of Luther.

Above, there are baroque columns between which are the sculpted images of the four evangelists, Saint Matthew, Saint John, Saint Mark and Saint Luke. In the central portion is the sculpture of the "Immaculate Conception Holy Mary of the Good Happening". On the pulpit's thorax is engraved in high relief the effigy of the Patron Saint of the parish: Saint Blaise; with pontifical clothing. Above this image is the bishop Mollinedo y Angulo's coat of arms. In the very adorned sounding board (it amplifies the voice of whom giving the sermon) are sculptures of the church's doctors, Saint Bonaventure, Saint Thomas of Aquinas, Saint Augustine, Saint Gregory the Great, Saint Jerome, Saint Bernard and Saint Francis of Sales. And finally, crowning the pulpit and supported by five archangels is the sculpture of Saint Paul of Tarsus (Carreño believes that it is Saint Thomas and some others that it is Jesus Christ) with a crucifix in his hand; before the feet of Saint Paul is the skull that is supposed to belong to the pulpit's author.

Likewise, the church's High Altar is imposing, carved in cedar wood and gilded with gold flakes. It has a mixed style in which the baroque twisted columns stand out. It was gilded and possibly also carved by Juan Tomas Tuyro Tupaq and his woodcarvers team. In its central portion is the Virgin of the Immaculate Conception and above a Saint Blaise effigy. On the eastern wall there is another altarpiece made by Tuyro Tupaq and his son Mateo towards 1678; it belongs to the "Virgin of the Good Happening" who is painted on the original piece of wall brought from the "Lirpuy-phaqcha" chapel. There are some other altarpieces belonging to Saint Blaise, Saint Joseph, and a dark Jesus Christ known as the "Lord of the Agony" that has movable arms and head; his dark color is because is covered with llama parchment. Over the side walls are 8 anonymous canvases with impressive gilded frames; they represent the martyrdom of Saint Blaise, bishop of Tucuman. Inside the baptistery there is a painting with a Jesus Christ having an evident female body. Toward the right side of the entrance is a crooked cross made in a single piece of Chachacomo wood (a native Andean tree). The church has, even more, a higher choir with balusters of gilded cedar wood.