Sentence:  One can even argue - though this is a delicate matter - that every justification existed for their returning the Public Lecture to the First Church , and so to suppress it , rather than <WSD>let</WSD> Parker use it as a sounding board for his propaganda when his turn should come to occupy it . 
Meaning of the word marked with <WSD> tags:  make it possible through a specific action or lack of action for something to happen