On 12 February 1527 Zwingli wrote his friend Conrad Sam. In that letter he remarks
“Archetelem” ante annos quinque scripsi ad episcopum Constantiensem, quo rationem reddidi doctrinę. Liber adeo mendose fuit excusus, ut nihil debeas de eo esse sollicitus; misissem tamen, si ullus superfuisset.
Sam should have read it before 1527… the wretch. Your friends ought to read what you write. Unless they aren’t really friends… (Let the reader understand).
Just to make the point, he remarks again concerning his latest work
Mitto librum “De officio praedicandi”.
Which is as much as to say- ‘this one you need to read now’.