On the north wall , there is a niche that hold a statue of the crucifix with a Christ image sculpted in ivory . Behind this , is another mural that depict the Juan Diego 's of Our Lady of Guadalupe . The Sacristy used to house Juan Diego 's cloak , upon which the Virgin 's image purportedly appear , but after massive flooding in 1629 , it was removed from the Sacristy to better protect it .