Returning from a trip to Edinburgh he falls in with a young Englishman calling himself Lovel, befriends him, and spends time showing him the local historical sights, though Oldbuck's antiquarian gullibility is comically exposed by an acquaintance, the beggar Edie Ochiltree.

When another member of the party, the fraudulent German alchemist Herman Dousterswivel, succeeds in getting money from Wardour to finance a search for the treasure Oldbuck warns his friend against the charlatan.

We learn that Oldbuck had once loved a certain Eveline Neville, who had preferred to secretly marry Glenallan, but the marriage had ended with the wife's suicide, the husband's nervous breakdown, and the spiriting away of their only son.

He writes on castrametation, the science of ancient fortification, and contributes papers on learned subjects to journals; he argues heatedly with his friends over the nature of the Pictish language; he buys overpriced land purely for the pleasure of owning the site of a Roman camp and of the battle of Mons Graupius.

[13] Scott himself tells us that the character was loosely based on a friend of his father's, one George Constable, a retired lawyer who lived at a country house called Wallace-Craigie, near Dundee.

He claimed that there is not a single incident in the novel which is borrowed from his real circumstances except the fact that he resided in an old house near a flourishing seaport, and that the Author chanced to witness a scene betwixt him and the female proprietor of a stage coach, very similar to that which commences the history of The Antiquary.

[4] The two men were equally capable of being taken in by fraudulent impositions on their credulity, as when Scott accepted the fake ballad “Barthram's Dirge” and a manufactured Latin legend about a spectre knight from his friend Robert Surtees.

[19] They were also equally prone to buying land purely for its historical associations, Scott being in the process of completing his acquisition of the entire wide-ranging site of the battle of Melrose while he was writing The Antiquary.

[26] Oldbuck's preference for publishing his scholarly papers and the proposed notes for Lovel's Caledoniad anonymously or pseudonymously recall the fact that The Antiquary, like all the earlier Waverley novels, first appeared without Scott's name.

[29] A. N. Wilson believed that if Scott had continued to quietly cultivate his friendships and the life of the mind like Oldbuck, rather than indulging a folie de grandeur like Wardour's, he would have died a happier man.

[34] The British Lady's Magazine and John Wilson Croker in the Quarterly Review agreed in thinking him a repetition of a character from an earlier Scott novel, though they differed as to whether this was the Baron of Bradwardine from Waverley or Counsellor Pleydell from Guy Mannering.

[35] The Edinburgh Review’s initial impression was that Oldbuck, as an “oddity”, was the great blemish on the novel, but later found that he “is so managed as to turn out both more interesting and more amusing than we had any reason to expect”.

[36] Lockhart agreed better with the second thoughts of the Edinburgh reviewer, Francis Jeffrey, than his first, going so far as to say that Scott had “nowhere displayed his highest art, that of skillful contrast, in greater perfection…than the oddities of Jonathan Oldbuck and his circle are relieved, on the one hand by the stately gloom of the Glenallans, on the other by the stern affliction of the poor fisherman”.

[45] Andrew Lang also had no doubts, calling him “perennially delightful”,[46] and the scholar Aubrey Bell cited Oldbuck in support of his and Georg Brandes' view that Scott was one of the finest drawers of character ever to have lived.