What does Leontes mean by saying that he is blessed and cursed in scene 2 Act 2 of "The Winter's Tale"?

Question

In the first scene of act II of The Winter's Tale, Leontes says:

How blest am I
In my iust 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 drinke; depart,
And yet partake no venome: (for his knowledge
Is not infected) but if one present
Th' abhor'd Ingredient to his eye, make knowne
How he hath drunke, he cracks his gorge, his sides
With violent Hefts: I haue drunke, and seene the Spider.
Camillo was his helpe in this, his Pandar:
There is a Plot against my Life, my Crowne;
All's true that is mistrusted: that false Villaine,
Whom I employ'd, was pre-employ'd by him:
He ha's discouer'd my Designe, and I
Remaine a pinch'd Thing; yea, a very Trick
For them to play at will: how came the Posternes
So easily open?

I tried to decode Leontes in his speech but to no avail.

1. What does he mean by saying that he is blessed? Does he claim to have divine aid?

2. He claims to haue drunke, and seene the Spider and he shares his knowledge of the details of the supposed plot. Why then does he speak earlier of not having enough knowledge, Alack, for lesser knowledge, how accurs'd, In being so blest? ? Can he mean here his not knowing of Camillo being pre-employed?

Answer 1

First, the meaning of “blest”. The sense here is “happy, fortunate”, which Leontes uses ironically. He is fortunate in the correctness of his “censure” (that is, his judgement or opinion) since he has forestalled (he believes) a “plot against my life, my crown”, and so he should be happy, but in fact he is miserable, as he believes the flight of Polixenes and Camillo has justified his suspicion of the infidelity of his wife Hermione.

Second, how to reconcile Leontes’ knowledge of the (supposed) plot with his “Alack, for lesser knowledge”. Samuel Johnson offered the following gloss that resolves the difficulty:

Alack, for lesser knowledge—] That is, O that my knowledge were less.

_{Samuel Johnson, ed. (1765). The Plays of William Shakespeare, volume 2, p. 255, footnote. London: J. and R. Tonson etc.}