4 He seeks, of all his drift the aimed end:
drift > intention; plot
5 Thereto his subtile engines he does bend,
subtile > subtle; sly, crafty engines > wiles
6 His practic wit, and his fair filed tongue,
practic > artful, cunning filed > smooth, polished
7 With thousand other sleights: for well he kenned
kenned > recognized; acknowledged
8 His credit now in doubtful balance hung;
credit > reputation; authority; credibility