The colloquial phrase that’s rich, coming from — means: that’s a surprisingly unfair criticism, considering that the person who has just made it has the same fault. (Here, the adjective rich means: preposterous, outrageous.)
This phrase occurs, for example, in the following from The Independent (London, England) of Friday 12th November 2021 [page 33]:
Robust on rule-breaking is a bit rich coming from the PM
CATHY NEWMAN
For a man who’s apparently spent a lifetime bending the rules, it took some chutzpah to say—as Boris Johnson did last night— that “those who break the rules must be investigated and should be punished”.
His comments came exactly a week after he sparked a Conservative revolt by pausing punishment for his friend Owen Paterson, who—according to the standards committee—broke the rules on lobbying.
The earliest occurrences that I have found of the phrase that’s rich, coming from — are as follows, in chronological order:
1-: From Metropolitan University, published in the Kentish Gazette, and General Weekly Journal for East and West Kent (Canterbury, Kent, England) of Tuesday 27th December 1836 [No. 6,964, page 2, column 4]—John Russell (1792-1878), 1st Earl Russell, was a British politician whose small stature was frequently the butt of jokes:
The charter for the Metropolitan University has been at length made public. It is directed to the Earl of Burlington, as Chancellor […]. Lord John Russell’s letter to the Earl of Burlington, on the occasion, is really a curiosity in its way. In mercy to his little lordship we refrain from publishing it; but the following extract will prove what sort of production it is. He assures Lord Burlington that the “New University of London is an institution destined to confer the distinctions justly due to proficiency in literature, science, or art, without imposing a test of RELIGIOUS OPINIONS, or binding by the fetters of the seventeenth century the talent and merit of the present enlightened age.” […] The sneer at the 17th century is peculiarly rich, coming from such a maniken of a statesman as Lord Johnny. The author of a shelved play, called Don Carlos, turns up his little nose at the age which produced Beaumont and Fletcher, Ben Johnson, Marlow, Shirley, and Shakspeare! He despises the age in which flourished Jeremy Taylor, Chillingworth, Cudworth, South, Barrow, Usher, Burnet, and Tillotson, divines; [&c.]!
2-: From an account of a banquet given in Derry, County Derry, Ireland, in honour of Charles William Vane (1778–1854), 3rd Marquess of Londonderry, published in The Pilot (Dublin, County Dublin, Ireland) of Monday 13th November 1837 [Vol. 9, page 3, column 3]:
The anile peer […] talked of Lord Palmerston holding office under successive administrations, and vaunted of his own disinterested independence. This was rather rich, coming from the very personage whose “zeal beyond discretion” to finger some of the public money, in the shape of a pension, forced a Tory premier (Liverpool) to answer the shameful application with “This is too bad.” The very hero who wished to cut and run from his creditors out to Russia, during Peel’s administration, until Wellington stoutly refused to damn the party by giving him the appointment.
3-: From an account of a lecture on the doctrine of transubstantiation, published in The Liverpool Mercury, and Lancashire General Advertiser (Liverpool, Lancashire, England) of Friday 21st May 1841 [Vol. 31, No. 1,567, page 6, column 5]:
The Rev. Fielding Ould, in his speech upon taking the chair, complained that Dr. Butler had come amongst them and disturbed the peace of the town. This is rich, indeed, coming from the quarter it does. So, according to the logic of the reverend gentleman, if he and his confreres, who are in the constant habit, both in their pulpits and at their amphitheatrical meetings of attacking and vilifying the religious creed of their neighbours, are exposed for such conduct.—“Oh!” they exclaim, “the peace of the town is disturbed!” The reverend gentleman seems to have forgotten the description of the beam and the mote in the Gospel. It is he and other importations of the like kind from the sister isle who are the real and genuine disturbers.
4-: From comments on a letter by Martin Van Buren (1782-1862), 8th President of the United States from 1837 to 1841, dated Friday 26th November 1841, published in the Daily Richmond Whig (Richmond, Virginia, USA) of Friday 25th November 1842 [Vol. 28, No. 126, page 2, column 3]—“they” apparently designates “those who desire a fair and full expression of the popular will”, which Martin Van Buren used in the preceding paragraph of his letter:
The next paragraph opens with a sentence which is rich, as coming from a man notoriously foisted into the Presidency by the will of his predecessor, not the choice of the people.
“The Presidency, above all others, seems to be a place which they determine shall wait their free will offering, and in respect to which they will neither allow themselves to be assailed by personal importunities nor permit their selection to be hastened or impeded by ex-parte * arrangements.”
* The adjective ex-parte means: made with respect to, or in the interest of, one side only.
5-: From Selected Items, published in the Vermont Gazette (Bennington, Vermont, USA) of Tuesday 11th June 1844 [Vol. 15, No. 24, page 3, column 3]:
The Lowell Journal talks about Com. Stewart’s ‘total unfitness’ for the presidency. This is very rich, coming from one who was a zealous supporter of Gen. Harrison.
6-: From the Brooklyn Evening Star (Brooklyn, New York, USA) of Monday 20th July 1846 [37th Year, No. 1,713, page 2, column 2]:
Pennsylvania Democracy.—The Democrats of Pennsylvania are very much like the doctor who was compelled to swallow his own medicine. They held a Great Tariff Meeting at Philadelphia on Saturday evening last, and passed numerous thundering Resolutions, in which they out whigged the whigs in condemning McKay’s bill and in defending the Tariff of 1842. The resolutions are very rich, as coming from democrats; and “would serve without essential variation” for a Whig meeting in Massachusetts!
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