This quote is from William Shakespeare’s play “Hamlet” and refers to the way guilt can manifest as jealousy and cause a person to reveal their own wrongdoing in an attempt to deflect suspicion.
The phrase “so full of artless jealousy is guilt” means that guilt often causes a person to become suspicious of others, even if they have no reason to be. This suspicion is “artless” or unskilled because it is not based on any evidence or logical reasoning, but rather on the guilty person’s own fear of being discovered.
The phrase “it spills itself in fearing to be spilt” means that the guilty person is so afraid of being caught that they may reveal their wrongdoing unintentionally. Just as a container that is too full will spill over if jostled, the guilty person may “spill” information about their guilt in their anxious attempts to avoid suspicion.
Overall, this quote suggests that guilt can cause a person to behave in ways that are self-defeating and ultimately reveal their wrongdoing. It also implies that the fear of being caught can be so overwhelming that it leads to irrational and suspicious behavior.