The phrase to teach one’s grandmother to suck eggs means to presume to advise a more experienced person.

Raw eggs, with or without a little seasoning, used to be a popular food and were regarded as healthy. Grandmothers obviously needed no instruction about how to drink them.

The phrase is first recorded in a translation from Spanish by Captain John Stevens (circa 1662-1726), titled The Comical Works of Don Francisco Quevedo¹, Author of the Visions (1707):

You would have me teach my Grandame to suck Eggs.

The word grandame, from grand and dame, means grandmother. Dating back to the early 13^th century, it is the oldest of the English terms of relationship formed with grand-.

(¹ Francisco Gómez de Quevedo y Villegas (1580-1645) was a prominent Spanish poet and satirist.)

The Irish satirist, poet and Anglican cleric Jonathan Swift (1667-1745) also used the phrase in A Complete Collection of Genteel and Ingenious Conversation, published in 1738 but written in the first decade of the 18^th century:

– Miss Notable: Lord! I have torn my Petticoat with your odious Romping. […]
– Mr. Neverout: I’ll mend it, Miss.
– Miss Notable: You mend it! go, teach your Grannam to suck Eggs.

This book by Jonathan Swift is a satire on the use of clichés: its purported author, Simon Wagstaff, “can faithfully assure the Reader, that there is not one single witty Phrase in this whole Collection, which hath not received the Stamp and Approbation of at least one hundred Years.” The phrase to teach one’s grandmother to suck eggs was therefore already proverbial in the early 18^th century.

A definition was given in Dictionarium Britannicum: Or a more Compleat Universal Etymological English Dictionary Than any Extant (1736 edition), by the English lexicographer Nathan Bailey (died 1742):

Teach your Grannum (Grandame) to suck Eggs. A Reproof to those, who think they have more Knowledge than the whole World, and will be ever and anon teaching those who have had more Experience than themselves.
The Scots say: Learn your Goodam to make Milk-Kail (Milk-Pottage) or, Teach your Father to get Bairns (Children). Latin: Sus Minervam. French: Les Oisons mènent les Oyes paître (i.e.) the Goslings lead the Geese to the Pasture. We say likewise, teach your Granny to grope her Goose. The Italians: I paperi voglion menar à bene l’oche.

The Italian phrase cited by this dictionary is properly i paperi voglion menare a bere l’oche and means the goslings want to take the geese to drink.

This dictionary also mentions the Latin phrase sus Minervam (docet), which means a sow, or a swine, teaches Minerva (Minerva was the Roman goddess of wisdom). This proverb was used in Latin literature to condemn the presumption of stupid and ignorant people who would undertake to instruct those from whom they themselves should take instruction.

This Latin phrase was cited, as well as another English proverb, by the English cleric and author Edward Topsell (circa 1572-1625) in The History of Four-footed Beasts and Serpents:

(1658 edition)
In Latin they say Sus Minervam, when an unlearned dunce goeth about to teach his better or a more learned man, then doth the Hog teach Pallas², or as we say in English, the foul Sow teach the fair Lady to spin.

(² Pallas: the patron goddess of Athens, typically allegorised into a personification of wisdom. Minerva was her Roman equivalent.)

Nathan Bailey also mentions the proverb teach your granny to grope her goose. A variant is found in A Dictionarie of the French and English Tongues (1611), a French-English dictionary compiled by Randle Cotgrave:

Apprendre aux poissons à nager. To teach fishes to swimme; (an idle, vaine, or needlesse labour) we say, to teach his grandame to grope ducks.

To grope a fowl means to use the fingers to measure the distance between its pelvic bones: if these are close together, it is not laying and can be consigned to the pot.

But, as John Greaves Nall noted in An etymological and comparative Glossary of the Dialect and Provincialisms of East-Anglia (1866) about the proverb teach your grandame to grope her ducks,

now-a-days the good old lady is taught ‘to suck eggs.’

In his French-English dictionary, Randle Cotgrave also mentioned the French proverbs l’oison n’est pas digne de montrer les pâquis à l’oie (the gosling is not worthy to show the pastures to the goose), les oisons mènent paître les oies (the goslings lead the geese to the pasture) and l’oie mène l’oison paître (the goose leads the gosling to the pasture):

– L’oison n’est pas digne de monstrer les pasquis à l’oye. (A checke for young men that presume to teach their elders.)
– Les oisons menent paistre les oyes : Prov. (Said when subiects gouerne their Princes, children their parents, meane men the Magistrates, and seruants or schollers their maisters; and is a note as well of weakenesse in the Geese, as of sawcinesse in the Goslings.)
– L’oye meine l’oison paistre: Prov. The Goose leads out the Gosling to the field; (contrarie to the former, and an argument of a well-proportioned gouernment.)