Q: Why is a monstrance not used for the Holy Thursday procession? Thanks.
A: As I point out in Glory in the Cross, the Vatican’s Circular Letter on Lent, Holy Week and Easter expressly forbids the use of the monstrance (55). The first purpose of reserving consecrated hosts on this night is to provide communion for Good Friday.
Adoration on Thursday night probably became popular as a way of introducing some drama into the commemoration of Holy Thursday. As Jesus asked the apostles to wait up with him, we imagine him saying the same to us. Unlike them, we keep watchful prayer. This isn’t Benediction or a Corpus Christi Procession. It’s the Triduum.