“Go, therefore, and make disciples of all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Spirit, teaching them to observe all that I have commanded you.” Matthew 28:19-20
There are several stories attributed to the symbol of the scalloped seashell and its association with St. James. One is that medieval pilgrims used shells to hold food or water instead of a bowl, and Compostela had become a popular pilgrimage site; another story is that while St. James’ remains were being transferred to Compostela a knight’s horse fell into a stream and emerged covered in shells.
Additionally, scallop shells were often used to dip into water for baptism. St. James, being a missionary pilgrim to Spain, is therefore associated with the scallop shell which is typically depicted on his clothing, especially a pilgrim hat.