Here is a typed Lenten sermon from February of 1988. It is marked up in red pen. He references a surgery that he experienced in September of 1987, which was likely the removal of cancer tissue from his upper back.
The Gospel listed is Mark 1:12-13, which corresponds to the The First Sunday of Lent in Year B of the Revised Common Lectionary. There is a quote from Meister Eckhart in this sermon, although the version of the quote I see on Goodreads(https://www.goodreads.com/quotes/27770-nothing-in-all-creation-is-so-like-god-as-stillness) references stillness instead of silence. The hymn following the sermon is listed as O Lord Throughout these Forty Days. I will embed a video of this hymn after the sermon.
A Process of Subtraction - 1 Lent B - 02/21/1988