Brewer's: Throwing an Old Shoe for Luck
(See under Shoe.)
“Now, for goode luck caste an old shoe after me.” —Haywood (1693-1756).
“Ay, with all my heart, there's an old shoe after you.” —The Parson's Wedding (Dodsley, vol. ix. p. 499).
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894