There seems to be much dispute between antiquarians as to the origin of both "Maunday" and "Shere," and of course the spelling has the usual vagaries. For instance The British Apollo (1709) says:--"Maunday is a corruption of the Latin word Mandatum, a command. The day is therefore so called, because as on that day our Saviour washed his disciples' feet, to teach them the great duty of being humble. And therefore he gives them in command to do as he had done, to imitate their Master in all proper instances of condescension and humility."
On the other hand "Maunday Thursday," says a writer in The Gentleman's Magazine (1779), "is the poor people's Thursday, from the Fr. maundier, to beg. The King's liberality to the poor on that Thursday in Lent [is at] a season when they are supposed to have lived very low. Maundiant is at this day in French a beggar." Which are we to believe? The preponderating weight of evidence seems to be in favour of the former.
In reference to "Shere," one authority says it is so called "for that in old Fathers' days the people would that day shere theyr hedes and clippe theyr berdes and pool theyr heedes, and so make them honest agenst Easter Day." But another writer in The Gentleman's Magazine (1779) finds a different origin for the word. "Maundy Thursday, called by Collier, Shier Thursday, Cotgrave calls by a word of the same sound and import, Sheere Thursday. Perhaps, for I can only go upon conjecture, as sheer means purus mundus, it may allude to the washing of the disciples' feet (John xiii. 5, et seq.), and be tantamount to clean. Please to observe too, that on that day they also washed the Altars: so that the term in question may allude to that business."
Here again one feels there is no other course open than to accept the word of the earlier authority. As to the events of the day, I cannot do better than transcribe a section from The Gentleman's Magazine for 1731:--
"Thursday, April 15, beind Maunday Thursday, there was distributed at the Banquetting House, Whitehall, to forty-eight poor men, and forty-eight poorwomen (the king's age forty-eight) boiled beef and shoulders of mutton, and small bowls of ale, which is called dinner; after that, large wooden platters of fish and loaves, viz. undressed, one large old ling, and one large dried cod; twelve red herrings, and twelve white herrings, and four half quarter loaves. Each person had one platter of this provision after which was distributed to them shoes, stockings, linen and woollen cloth, and leathern bags, with one penny, two penny, three penny, and four penny pieces of silver, and shillings; to each about four pounds in value. His Grace the Lord Archbishop of York, Lord High Almoner, performed the annual ceremony of washing the feet of a certain number of poor in the Royal Chapel, Whitehall, which was formerly done by the kings themselves, in imitation of our Saviour's pattern of humility, etc. James the Second was the last king who performed this in person."
But some Catholic monarchs still persevere in this pious act, even to the washing of beggars' feet. In England, the king's Maundy is given at Westminster Abbey at a specially convened service, and those who receive it are carefully chosen from London parishes.