Elia ponders the origins of saying grace before eating dinner, thinking back to the significance this probably held in the day of hunters, when a group of people eating meat was grateful for the day's bounty. But in these modern times, Lamb inquires, why do people say grace before eating food but not before doing anything else for which they are grateful? Why not before a stroll at night time or meeting up with a friend, or before reading Shakespeare and Milton?
Similarly, saying grace makes sense at a poor person's table, where the poor man sits before a meal that he's not sure he will have the next day. The rich, on the other hand, don't understand the nature of the grace they are saying, with no real risk of going hungry. A simple plate of mutton and turnips seems befitting of saying grace, since its modest offerings bespeak modest means. The feasts at rich men's tables, on the other hand, are excesses which make a mockery of God's gifts.
Elia recounts the falseness he has witnessed when rich men have sat down to great feasts and taken moments to say grace before their meals. When he has been asked if he prefers that men simply start eating like hogs at the trough instead of giving their thanks to the Giver, Elia says that he would simply prefer that men would ask them to indeed think about their Giver and act less like hogs. He says that the proper reason for grace is sustenance, and not relishes, saying that extravagances should be even more genuine occasions for grace, not simply rote indulgences where gratefulness is travestied.
Elia mentions his favorite satire of feasts, recounted in Milton's Paradise Lost when Satan gains power. Satan lays out an extravagant feast for those whom he wants to tempt, inspiring boundless appetites in those partaking. This is contrasted with Elijah, who flees to the desert and eats what he can, his appetite always sated. Elia doesn't recount this in the name of some puritanical devotion to eating a spare diet, but to illustrate the paradox of saying grace when wildly indulging. He does not agree with flippant jokes when saying grace, but closes by recounting a tale in which Jesus turns his followers' dinner into trousers for children, satisfying the needs of children with the bounty of those who were doing just fine.
This essay is notable for encapsulating two of Charles Lamb's preoccupations: hypocrisy in religion and Milton. The essay hinges on his recounting of a passage in Paradise Lost in which Satan offers an extravagant feast as a temptation, contrasted with an ascetic approach to eating taken by the prophet Elijah. While Lamb very clearly explains the significance of this passage as part of his argument, he does not elaborate on the similarities between himself and Milton which make him so sympathetic to the author of Paradise Lost.
Milton, like Lamb, was an idiosyncratic Christian. He was pious, but pious on exactly his own terms. Paradise Lost was written from the position of critiquing the Stuart monarchy that ruled at the time in Britain, and Lamb similarly addresses his religious convictions through a series of critiques throughout his essays. Milton, as the writer of a Biblical epic that doubled as a takedown of the monarch who arrested him, was a fearless individualist. That individualism would become a Romantic ideal, and Lamb was likely inspired by Milton's brave denunciation of hypocrisy when writing his own unique takes on the mores 18th- and 19th-century British society.
There is another inter-textual relationship worth elaborating on here: the essay's similarity to those of Michel de Montaigne, the French writer who created the the essay form. Montaigne's essays were often his attempts to think through the specific issue he chose as his topic (the word "essay" derives from essayer, French for "to try"). "Grace Before Meat" sees Lamb doing similar work, grappling with an idea while offering no real resolution on the matter. In this sense, "Grace Before Meat" is one of Lamb's more classical essays, as it simply shows Lamb trying to explain his complex views on a certain topic, in the process critiquing wider societal ills such as the habits of the rich while assessing his own imperfect predilections.