Read it through once

LEONTES. How blest am I In my just censure, in my true opinion! Alack, for lesser knowledge! How accurs’d In being so blest! There may be in the cup A spider steep’d, and one may drink, depart, And yet partake no venom, for his knowledge Is not infected; but if one present Th’ abhorr’d ingredient to his eye, make known How he hath drunk, he cracks his gorge, his sides, With violent hefts. I have drunk, and seen the spider. Camillo was his help in this, his pander. There is a plot against my life, my crown; All’s true that is mistrusted. That false villain Whom I employ’d, was pre-employ’d by him. He has discover’d my design, and I Remain a pinch’d thing; yea, a very trick For them to play at will. How came the posterns So easily open?