Listen to Sean Barret reading the sestet of Milton's "On his Blindness".
Milton's sequence of clauses "His state /Is kingly: thousands at his bidding speed" is exceptionally difficult to perform rhythmically. The shorter a phrase, the more it resists being stretched over a prosodic boundary. The sentence "His state is kingly" contains only five syllables, but is stretched over a line boundary, assigning two very short syntactic fragments to either side. The sequence "thousands at his bidding speed" is stretched over a caesura, that intrudes upon it after the second syllable ("thousands"). In his reading of this hard-to-perform poem, Sean Barrett offers satisfactory solutions to most of the enjambments (as, for instance, in "Who best / Bear His mild yoke"). However, regarding the sequence "His state // Is kingly: thousands / at his bidding speed" his performance is quite disappointing. He isolates the sentence "His state is kingly" from both the preceding and the ensuing sentences by longish pauses. The word "state" is brief, and subordinated by a low intonation contour to the predicate "is kingly", suppressing any suggestion that "state" may end a versification unit. Likewise, the subsequent longish pause and the absence of any cue for discontinuity after "thousands" suppresses any suggestion that we may face here an iambic pentameter line articulated by a caesura. We simply perceive two unmetered prose utterances "His state is kingly", and "Thousands at his bidding speed". Listen to his reading of these lines.
Some other performers, on the contrary, observe a straightforward pause after "His state". Listen to Anonymus' and Leon Mire's readings of this sentence. Notice that though the two readings differ in nuances, they apply essentially the same intonation contours.