How we cite our quotes:
The gods are just, and of our pleasant vices
Make instruments to plague us.
The dark and vicious place where thee he got
Cost him his eyes. (5.3.4)
Here, Edgar has mortally wounded his evil brother Edmund. As if to explain, Edgar says "the gods are just" because they punish humans for their wrong doings. This seems to suggest that Edmund deserved what he got (a stab to the guts) and it also suggests that Gloucester, Edmund's father, got what he deserved for having an affair with Edmund's mother. (Gloucester's eyes were plucked out after he was accused of treason and, he fathered a wicked child, Edmund, who betrayed him.)
What's significant about this passage is the way Edgar refers to the body of Edmund's mother as a "dark and vicious place where" Edmund was begot. It seems to imply that all the bad things in the world (like the wicked Edmund, for example), spring from the loins of women. Gloucester implies something similar at the play's beginning, which we discuss in the following passage (1.1.3).
Sir, this young fellow's mother could [conceive]: whereupon
she grew round-wombed, and had, indeed, sir, a son
for her cradle ere she had a husband for her bed.
Do you smell a fault?
I cannot wish the fault undone, the issue of it
being so proper. (1.1.3)
This is an awfully strange way to open the play, don't you think? Just a few lines into King Lear, Gloucester begins to crack dirty jokes about the mother of his illegitimate child, Edmund. When he asks Kent if he "smell[s] a fault," he's referring to his son, who is standing right there. Gloucester's use of the term "fault" means a couple of things: 1) a sin – Edmund was conceived out of wedlock and, as we soon see, Edmund also turns out to be wicked ; 2) female genitals-Gloucester's implying that Edmund "smells" like his mother's vagina.
So, why are we talking about this crude joke? Well, it turns out that, in King Lear, Edmund is frequently associated with the female body. At 5.3.4 (see passage above), Edgar associates Edmund with the "dark and vicious place" where Edmund was begot. This also echo's a statement Lear makes when he's angry at his daughters – below women's "waist[s]," "there's hell, there's darkness, there's the sulphurous pit (4.6.6). In other words, the female body is associated "sin" and "hell."