(St.). Patron saint of artists and smiths. He was a famous worker in gold and silver, and was made Bishop of Noyon in the reign of Dagobert. Probably the St. Eloi of Chaucer's Prioress was St. Louis (St. 'Loy)
Ther was also a nonne, a prioresse, That of hire smylyng was ful symple and coy! Hire grettest ooth was but by Seynt Loy.
We find reference to “Seynt Loy” again in verse 7143.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
More on Eloi from Fact Monster: