“If a building is honest, the architecture is religious,” said Finnish-American architect Eliel Saarinen. Such words were never so true as in his 1949 design of Christ Church Lutheran in Minneapolis, which his son Eero added to in 1962 with the design of an education wing.

On Sunday, the church will commemorate Eero Saarinen’s 100th birthday with “Fathers, Sons and Hidden Treasures.” The free event includes a lecture by Nick Hayes, professor of history at the College of Saint Benedict and Saint John’s University, and University Chair in Critical Thinking at SJU. Hayes’ father, Mark, was an architect who worked with Eliel Saarinen in 1949 during the original construction of Christ Church.

The event also includes an exhibition from the church’s archive of architectural drawings — including rarely seen original drawings by Eliel and Eero Saarinen. And of course, visitors will be welcome to tour the sanctuary and adjacent education wing.

“Fathers, Sons and Hidden Treasures.” 3 p.m., Sunday. Free. Christ Church Lutheran, 3244 34th Avenue South, Minneapolis.