Altarpiece I is sectioned into three parts: the altarpiece that is featured prominently on the right side of the painting, a depiction of a crucifix that is rendered on the left side of the painting, and a series of icons that decorate the top boarder of the artwork. Both the altarpiece and the crucifix are themes that are carried throughout Philipson’s catalogue, with the crucifix entering his oeuvre in the 60s, and the Mexican altarpiece featuring in many of his works in the 70s. Philipson was inspired to create this artwork, and numerous others, during his stay as a visiting professor at the University of Colorado in 1963. During this period, he travelled around the United States with his most memorable trip visiting New Mexico. It is here where he visited El Santuario in Chimayo which houses the altarpiece depicted in this painting. Philipson was inspired by the altarpiece and its deeply majestic and magnificent nature. This altarpiece would appear in numerous artworks produced by Philipson throughout the 70s with religious iconography becoming a mainstay in his catalogue. Altarpiece I was donated to the Cathedral by Philipson in 1972, where it has been on display since.