I will—
Acquaint you with a perfect spy o' the time.
Accordingly a third murderer joins them afterwards at the place of action.
Perfect is well instructed, or well informed, as in this play,
Though in your state of honour I am perfect.
though I am well acquainted with your quality and rank. [Warburton explained this as "the critical juncture">[ How the critical juncture is the spy o' the time I know not, but I think my own conjecture right.
III.ii.38 (467,1) nature's copy's not eternal] The copy, the lease, by which they hold their lives from nature, has its time of termination limited.
III.iii.1 (469,6) But who did bid thee join with us?] The meaning of this abrupt dialogue is this. The perfect spy, mentioned by Macbeth in the foregoing scene, has, before they enter upon the stage, given them the directions which were promised at the time of their agreement; yet one of the murderers suborned suspects him of intending to betray them; the other observes, that, by his exact knowledge of what they were to do, he appears to be employed by Macbeth, and needs not be mistrusted.
III.iv.1 (470,9) You know your own degrees, sit down: at first,/And last the hearty welcome] As this passage stands [sit down:/At first and last], not only the numbers are very imperfect, but the sense, if any can be found, weak and contemptible. The numbers will be improved by reading,
—sit down at first,