"The Immaculata is herself a monstrance, meaning transparent of and to God," we read in the Marian Library of the University of Dayton. "It is her honor to make God visible through her sinlessness and as dwelling place of the Holy Spirit and her Son Jesus Christ.  Mary is, according to 2 Timothy 21 'a vessel for lofty use (vas in honorem), dedicated, beneficial to the master of the house'."  

The master of the house here is Christ himself, present in the host held by the “vessel of honor," his mother Mary.  She is indeed, as Immaculata, the work of the Almighty One, and thus an “admirable vessel." 

For Reflection: 

When Mary appears in an apparition, seers remark about the luminous quality that accompanies her or emanates through her. Everything about Mary refers to her Son. As Christ-bearer, she always makes Jesus present. How have you experienced this in your own life? To what extent has Mary led you in the mysteries of salvation? Journal about the most profound of these experiences.